Examples¶
Get started¶
A button with a label and react on click event¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_BTN
static void btn_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * btn = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
static uint8_t cnt = 0;
cnt++;
/*Get the first child of the button which is the label and change its text*/
lv_obj_t * label = lv_obj_get_child(btn, 0);
lv_label_set_text_fmt(label, "Button: %d", cnt);
}
}
/**
* Create a button with a label and react on click event.
*/
void lv_example_get_started_1(void)
{
lv_obj_t * btn = lv_btn_create(lv_scr_act()); /*Add a button the current screen*/
lv_obj_set_pos(btn, 10, 10); /*Set its position*/
lv_obj_set_size(btn, 120, 50); /*Set its size*/
lv_obj_add_event_cb(btn, btn_event_cb, LV_EVENT_ALL, NULL); /*Assign a callback to the button*/
lv_obj_t * label = lv_label_create(btn); /*Add a label to the button*/
lv_label_set_text(label, "Button"); /*Set the labels text*/
lv_obj_center(label);
}
#endif
class CounterBtn():
def __init__(self):
self.cnt = 0
#
# Create a button with a label and react on click event.
#
btn = lv.btn(lv.scr_act()) # Add a button the current screen
btn.set_pos(10, 10) # Set its position
btn.set_size(120, 50) # Set its size
btn.align(lv.ALIGN.CENTER,0,0)
btn.add_event_cb(self.btn_event_cb, lv.EVENT.ALL, None) # Assign a callback to the button
label = lv.label(btn) # Add a label to the button
label.set_text("Button") # Set the labels text
label.center()
def btn_event_cb(self,evt):
code = evt.get_code()
btn = evt.get_target()
if code == lv.EVENT.CLICKED:
self.cnt += 1
# Get the first child of the button which is the label and change its text
label = btn.get_child(0)
label.set_text("Button: " + str(self.cnt))
counterBtn = CounterBtn()
Create styles from scratch for buttons¶
C code
GitHub#include "../lv_examples.h"
#if LV_USE_BTN && LV_BUILD_EXAMPLES
static lv_style_t style_btn;
static lv_style_t style_btn_pressed;
static lv_style_t style_btn_red;
static lv_color_t darken(const lv_color_filter_dsc_t * dsc, lv_color_t color, lv_opa_t opa)
{
LV_UNUSED(dsc);
return lv_color_darken(color, opa);
}
static void style_init(void)
{
/*Create a simple button style*/
lv_style_init(&style_btn);
lv_style_set_radius(&style_btn, 10);
lv_style_set_bg_opa(&style_btn, LV_OPA_COVER);
lv_style_set_bg_color(&style_btn, lv_palette_lighten(LV_PALETTE_GREY, 3));
lv_style_set_bg_grad_color(&style_btn, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_bg_grad_dir(&style_btn, LV_GRAD_DIR_VER);
lv_style_set_border_color(&style_btn, lv_color_black());
lv_style_set_border_opa(&style_btn, LV_OPA_20);
lv_style_set_border_width(&style_btn, 2);
lv_style_set_text_color(&style_btn, lv_color_black());
/*Create a style for the pressed state.
*Use a color filter to simply modify all colors in this state*/
static lv_color_filter_dsc_t color_filter;
lv_color_filter_dsc_init(&color_filter, darken);
lv_style_init(&style_btn_pressed);
lv_style_set_color_filter_dsc(&style_btn_pressed, &color_filter);
lv_style_set_color_filter_opa(&style_btn_pressed, LV_OPA_20);
/*Create a red style. Change only some colors.*/
lv_style_init(&style_btn_red);
lv_style_set_bg_color(&style_btn_red, lv_palette_main(LV_PALETTE_RED));
lv_style_set_bg_grad_color(&style_btn_red, lv_palette_lighten(LV_PALETTE_RED, 3));
}
/**
* Create styles from scratch for buttons.
*/
void lv_example_get_started_2(void)
{
/*Initialize the style*/
style_init();
/*Create a button and use the new styles*/
lv_obj_t * btn = lv_btn_create(lv_scr_act());
/* Remove the styles coming from the theme
* Note that size and position are also stored as style properties
* so lv_obj_remove_style_all will remove the set size and position too */
lv_obj_remove_style_all(btn);
lv_obj_set_pos(btn, 10, 10);
lv_obj_set_size(btn, 120, 50);
lv_obj_add_style(btn, &style_btn, 0);
lv_obj_add_style(btn, &style_btn_pressed, LV_STATE_PRESSED);
/*Add a label to the button*/
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text(label, "Button");
lv_obj_center(label);
/*Create another button and use the red style too*/
lv_obj_t * btn2 = lv_btn_create(lv_scr_act());
lv_obj_remove_style_all(btn2); /*Remove the styles coming from the theme*/
lv_obj_set_pos(btn2, 10, 80);
lv_obj_set_size(btn2, 120, 50);
lv_obj_add_style(btn2, &style_btn, 0);
lv_obj_add_style(btn2, &style_btn_red, 0);
lv_obj_add_style(btn2, &style_btn_pressed, LV_STATE_PRESSED);
lv_obj_set_style_radius(btn2, LV_RADIUS_CIRCLE, 0); /*Add a local style too*/
label = lv_label_create(btn2);
lv_label_set_text(label, "Button 2");
lv_obj_center(label);
}
#endif
#
# Create styles from scratch for buttons.
#
style_btn = lv.style_t()
style_btn_red = lv.style_t()
style_btn_pressed = lv.style_t()
# Create a simple button style
style_btn.init()
style_btn.set_radius(10)
style_btn.set_bg_opa(lv.OPA.COVER)
style_btn.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 3))
style_btn.set_bg_grad_color(lv.palette_main(lv.PALETTE.GREY))
style_btn.set_bg_grad_dir(lv.GRAD_DIR.VER)
# Add a border
style_btn.set_border_color(lv.color_white())
style_btn.set_border_opa(lv.OPA._70)
style_btn.set_border_width(2)
# Set the text style
style_btn.set_text_color(lv.color_white())
# Create a red style. Change only some colors.
style_btn_red.init()
style_btn_red.set_bg_color(lv.palette_main(lv.PALETTE.RED))
style_btn_red.set_bg_grad_color(lv.palette_lighten(lv.PALETTE.RED, 2))
# Create a style for the pressed state.
style_btn_pressed.init()
style_btn_pressed.set_bg_color(lv.palette_main(lv.PALETTE.BLUE))
style_btn_pressed.set_bg_grad_color(lv.palette_darken(lv.PALETTE.RED, 3))
# Create a button and use the new styles
btn = lv.btn(lv.scr_act()) # Add a button the current screen
# Remove the styles coming from the theme
# Note that size and position are also stored as style properties
# so lv_obj_remove_style_all will remove the set size and position too
btn.remove_style_all() # Remove the styles coming from the theme
btn.set_pos(10, 10) # Set its position
btn.set_size(120, 50) # Set its size
btn.add_style(style_btn, 0)
btn.add_style(style_btn_pressed, lv.STATE.PRESSED)
label = lv.label(btn) # Add a label to the button
label.set_text("Button") # Set the labels text
label.center()
# Create another button and use the red style too
btn2 = lv.btn(lv.scr_act())
btn2.remove_style_all() # Remove the styles coming from the theme
btn2.set_pos(10, 80) # Set its position
btn2.set_size(120, 50) # Set its size
btn2.add_style(style_btn, 0)
btn2.add_style(style_btn_red, 0)
btn2.add_style(style_btn_pressed, lv.STATE.PRESSED)
btn2.set_style_radius(lv.RADIUS.CIRCLE, 0) # Add a local style
label = lv.label(btn2) # Add a label to the button
label.set_text("Button 2") # Set the labels text
label.center()
Create a slider and write its value on a label¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SLIDER
static lv_obj_t * label;
static void slider_event_cb(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
/*Refresh the text*/
lv_label_set_text_fmt(label, "%"LV_PRId32, lv_slider_get_value(slider));
lv_obj_align_to(label, slider, LV_ALIGN_OUT_TOP_MID, 0, -15); /*Align top of the slider*/
}
/**
* Create a slider and write its value on a label.
*/
void lv_example_get_started_3(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_scr_act());
lv_obj_set_width(slider, 200); /*Set the width*/
lv_obj_center(slider); /*Align to the center of the parent (screen)*/
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL); /*Assign an event function*/
/*Create a label above the slider*/
label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "0");
lv_obj_align_to(label, slider, LV_ALIGN_OUT_TOP_MID, 0, -15); /*Align top of the slider*/
}
#endif
def slider_event_cb(evt):
slider = evt.get_target()
# Refresh the text
label.set_text(str(slider.get_value()))
#
# Create a slider and write its value on a label.
#
# Create a slider in the center of the display
slider = lv.slider(lv.scr_act())
slider.set_width(200) # Set the width
slider.center() # Align to the center of the parent (screen)
slider.add_event_cb(slider_event_cb, lv.EVENT.VALUE_CHANGED, None) # Assign an event function
# Create a label above the slider
label = lv.label(lv.scr_act())
label.set_text("0")
label.align_to(slider, lv.ALIGN.OUT_TOP_MID, 0, -15) # Align below the slider
Styles¶
Size styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Using the Size, Position and Padding style properties
*/
void lv_example_style_1(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
/*Make a gradient*/
lv_style_set_width(&style, 150);
lv_style_set_height(&style, LV_SIZE_CONTENT);
lv_style_set_pad_ver(&style, 20);
lv_style_set_pad_left(&style, 5);
lv_style_set_x(&style, lv_pct(50));
lv_style_set_y(&style, 80);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label, "Hello");
}
#endif
#
# Using the Size, Position and Padding style properties
#
style = lv.style_t()
style.init()
style.set_radius(5)
# Make a gradient
style.set_width(150)
style.set_height(lv.SIZE.CONTENT)
style.set_pad_ver(20)
style.set_pad_left(5)
style.set_x(lv.pct(50))
style.set_y(80)
# Create an object with the new style
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
label = lv.label(obj)
label.set_text("Hello")
Background styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the background style properties
*/
void lv_example_style_2(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
/*Make a gradient*/
lv_style_set_bg_opa(&style, LV_OPA_COVER);
static lv_grad_dsc_t grad;
grad.dir = LV_GRAD_DIR_VER;
grad.stops_count = 2;
grad.stops[0].color = lv_palette_lighten(LV_PALETTE_GREY, 1);
grad.stops[1].color = lv_palette_main(LV_PALETTE_BLUE);
/*Shift the gradient to the bottom*/
grad.stops[0].frac = 128;
grad.stops[1].frac = 192;
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
#
# Using the background style properties
#
style = lv.style_t()
style.init()
style.set_radius(5)
# Make a gradient
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 1))
style.set_bg_grad_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_bg_grad_dir(lv.GRAD_DIR.VER)
# Shift the gradient to the bottom
style.set_bg_main_stop(128)
style.set_bg_grad_stop(192)
# Create an object with the new style
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
obj.center()
Border styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the border style properties
*/
void lv_example_style_3(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 10);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add border to the bottom+right*/
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_width(&style, 5);
lv_style_set_border_opa(&style, LV_OPA_50);
lv_style_set_border_side(&style, LV_BORDER_SIDE_BOTTOM | LV_BORDER_SIDE_RIGHT);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
#
# Using the border style properties
#
style = lv.style_t()
style.init()
# Set a background color and a radius
style.set_radius(10)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 1))
# Add border to the bottom+right
style.set_border_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_border_width(5)
style.set_border_opa(lv.OPA._50)
style.set_border_side(lv.BORDER_SIDE.BOTTOM | lv.BORDER_SIDE.RIGHT)
# Create an object with the new style
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
obj.center()
Outline styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the outline style properties
*/
void lv_example_style_4(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add outline*/
lv_style_set_outline_width(&style, 2);
lv_style_set_outline_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_outline_pad(&style, 8);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
#
# Using the outline style properties
#
style = lv.style_t()
style.init()
# Set a background color and a radius
style.set_radius(5)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 1))
# Add outline
style.set_outline_width(2)
style.set_outline_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_outline_pad(8)
# Create an object with the new style
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
obj.center()
Shadow styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the Shadow style properties
*/
void lv_example_style_5(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add a shadow*/
lv_style_set_shadow_width(&style, 55);
lv_style_set_shadow_color(&style, lv_palette_main(LV_PALETTE_BLUE));
// lv_style_set_shadow_ofs_x(&style, 10);
// lv_style_set_shadow_ofs_y(&style, 20);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
#
# Using the Shadow style properties
#
style = lv.style_t()
style.init()
# Set a background color and a radius
style.set_radius(5)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 1))
# Add a shadow
style.set_shadow_width(8)
style.set_shadow_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_shadow_ofs_x(10)
style.set_shadow_ofs_y(20)
# Create an object with the new style
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
obj.center()
Image styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Using the Image style properties
*/
void lv_example_style_6(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 3));
lv_style_set_border_width(&style, 2);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_img_recolor(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_img_recolor_opa(&style, LV_OPA_50);
lv_style_set_transform_angle(&style, 300);
/*Create an object with the new style*/
lv_obj_t * obj = lv_img_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
LV_IMG_DECLARE(img_cogwheel_argb);
lv_img_set_src(obj, &img_cogwheel_argb);
lv_obj_center(obj);
}
#endif
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../assets/img_cogwheel_argb.png', 'rb') as f:
png_data = f.read()
except:
print("Could not find img_cogwheel_argb.png")
sys.exit()
img_cogwheel_argb = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
#
# Using the Image style properties
#
style = lv.style_t()
style.init()
# Set a background color and a radius
style.set_radius(5)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 3))
style.set_border_width(2)
style.set_border_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_img_recolor(lv.palette_main(lv.PALETTE.BLUE))
style.set_img_recolor_opa(lv.OPA._50)
# style.set_transform_angle(300)
# Create an object with the new style
obj = lv.img(lv.scr_act())
obj.add_style(style, 0)
obj.set_src(img_cogwheel_argb)
obj.center()
Text styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
/**
* Using the text style properties
*/
void lv_example_style_8(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 2));
lv_style_set_border_width(&style, 2);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_pad_all(&style, 10);
lv_style_set_text_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_text_letter_space(&style, 5);
lv_style_set_text_line_space(&style, 20);
lv_style_set_text_decor(&style, LV_TEXT_DECOR_UNDERLINE);
/*Create an object with the new style*/
lv_obj_t * obj = lv_label_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
lv_label_set_text(obj, "Text of\n"
"a label");
lv_obj_center(obj);
}
#endif
#
# Using the text style properties
#
style = lv.style_t()
style.init()
style.set_radius(5)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_lighten(lv.PALETTE.GREY, 3))
style.set_border_width(2)
style.set_border_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_pad_all(10)
style.set_text_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_text_letter_space(5)
style.set_text_line_space(20)
style.set_text_decor(lv.TEXT_DECOR.UNDERLINE)
# Create an object with the new style
obj = lv.label(lv.scr_act())
obj.add_style(style, 0)
obj.set_text("Text of\n"
"a label")
obj.center()
Line styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LINE
/**
* Using the line style properties
*/
void lv_example_style_9(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_line_color(&style, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_line_width(&style, 6);
lv_style_set_line_rounded(&style, true);
/*Create an object with the new style*/
lv_obj_t * obj = lv_line_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
static lv_point_t p[] = {{10, 30}, {30, 50}, {100, 0}};
lv_line_set_points(obj, p, 3);
lv_obj_center(obj);
}
#endif
#
# Using the line style properties
#
style = lv.style_t()
style.init()
style.set_line_color(lv.palette_main(lv.PALETTE.GREY))
style.set_line_width(6)
style.set_line_rounded(True)
# Create an object with the new style
obj = lv.line(lv.scr_act())
obj.add_style(style, 0)
p = [ {"x":10, "y":30},
{"x":30, "y":50},
{"x":100, "y":0}]
obj.set_points(p, 3)
obj.center()
Transition¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Creating a transition
*/
void lv_example_style_10(void)
{
static const lv_style_prop_t props[] = {LV_STYLE_BG_COLOR, LV_STYLE_BORDER_COLOR, LV_STYLE_BORDER_WIDTH, 0};
/* A default transition
* Make it fast (100ms) and start with some delay (200 ms)*/
static lv_style_transition_dsc_t trans_def;
lv_style_transition_dsc_init(&trans_def, props, lv_anim_path_linear, 100, 200, NULL);
/* A special transition when going to pressed state
* Make it slow (500 ms) but start without delay*/
static lv_style_transition_dsc_t trans_pr;
lv_style_transition_dsc_init(&trans_pr, props, lv_anim_path_linear, 500, 0, NULL);
static lv_style_t style_def;
lv_style_init(&style_def);
lv_style_set_transition(&style_def, &trans_def);
static lv_style_t style_pr;
lv_style_init(&style_pr);
lv_style_set_bg_color(&style_pr, lv_palette_main(LV_PALETTE_RED));
lv_style_set_border_width(&style_pr, 6);
lv_style_set_border_color(&style_pr, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_transition(&style_pr, &trans_pr);
/*Create an object with the new style_pr*/
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style_def, 0);
lv_obj_add_style(obj, &style_pr, LV_STATE_PRESSED);
lv_obj_center(obj);
}
#endif
#
# Creating a transition
#
props = [lv.STYLE.BG_COLOR, lv.STYLE.BORDER_COLOR, lv.STYLE.BORDER_WIDTH, 0]
# A default transition
# Make it fast (100ms) and start with some delay (200 ms)
trans_def = lv.style_transition_dsc_t()
trans_def.init(props, lv.anim_t.path_linear, 100, 200, None)
# A special transition when going to pressed state
# Make it slow (500 ms) but start without delay
trans_pr = lv.style_transition_dsc_t()
trans_pr.init(props, lv.anim_t.path_linear, 500, 0, None)
style_def = lv.style_t()
style_def.init()
style_def.set_transition(trans_def)
style_pr = lv.style_t()
style_pr.init()
style_pr.set_bg_color(lv.palette_main(lv.PALETTE.RED))
style_pr.set_border_width(6)
style_pr.set_border_color(lv.palette_darken(lv.PALETTE.RED, 3))
style_pr.set_transition(trans_pr)
# Create an object with the new style_pr
obj = lv.obj(lv.scr_act())
obj.add_style(style_def, 0)
obj.add_style(style_pr, lv.STATE.PRESSED)
obj.center()
Using multiple styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Using multiple styles
*/
void lv_example_style_11(void)
{
/*A base style*/
static lv_style_t style_base;
lv_style_init(&style_base);
lv_style_set_bg_color(&style_base, lv_palette_main(LV_PALETTE_LIGHT_BLUE));
lv_style_set_border_color(&style_base, lv_palette_darken(LV_PALETTE_LIGHT_BLUE, 3));
lv_style_set_border_width(&style_base, 2);
lv_style_set_radius(&style_base, 10);
lv_style_set_shadow_width(&style_base, 10);
lv_style_set_shadow_ofs_y(&style_base, 5);
lv_style_set_shadow_opa(&style_base, LV_OPA_50);
lv_style_set_text_color(&style_base, lv_color_white());
lv_style_set_width(&style_base, 100);
lv_style_set_height(&style_base, LV_SIZE_CONTENT);
/*Set only the properties that should be different*/
static lv_style_t style_warning;
lv_style_init(&style_warning);
lv_style_set_bg_color(&style_warning, lv_palette_main(LV_PALETTE_YELLOW));
lv_style_set_border_color(&style_warning, lv_palette_darken(LV_PALETTE_YELLOW, 3));
lv_style_set_text_color(&style_warning, lv_palette_darken(LV_PALETTE_YELLOW, 4));
/*Create an object with the base style only*/
lv_obj_t * obj_base = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj_base, &style_base, 0);
lv_obj_align(obj_base, LV_ALIGN_LEFT_MID, 20, 0);
lv_obj_t * label = lv_label_create(obj_base);
lv_label_set_text(label, "Base");
lv_obj_center(label);
/*Create another object with the base style and earnings style too*/
lv_obj_t * obj_warning = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj_warning, &style_base, 0);
lv_obj_add_style(obj_warning, &style_warning, 0);
lv_obj_align(obj_warning, LV_ALIGN_RIGHT_MID, -20, 0);
label = lv_label_create(obj_warning);
lv_label_set_text(label, "Warning");
lv_obj_center(label);
}
#endif
#
# Using multiple styles
#
# A base style
style_base = lv.style_t()
style_base.init()
style_base.set_bg_color(lv.palette_main(lv.PALETTE.LIGHT_BLUE))
style_base.set_border_color(lv.palette_darken(lv.PALETTE.LIGHT_BLUE, 3))
style_base.set_border_width(2)
style_base.set_radius(10)
style_base.set_shadow_width(10)
style_base.set_shadow_ofs_y(5)
style_base.set_shadow_opa(lv.OPA._50)
style_base.set_text_color(lv.color_white())
style_base.set_width(100)
style_base.set_height(lv.SIZE.CONTENT)
# Set only the properties that should be different
style_warning = lv.style_t()
style_warning.init()
style_warning.set_bg_color(lv.palette_main(lv.PALETTE.YELLOW))
style_warning.set_border_color(lv.palette_darken(lv.PALETTE.YELLOW, 3))
style_warning.set_text_color(lv.palette_darken(lv.PALETTE.YELLOW, 4))
# Create an object with the base style only
obj_base = lv.obj(lv.scr_act())
obj_base.add_style(style_base, 0)
obj_base.align(lv.ALIGN.LEFT_MID, 20, 0)
label = lv.label(obj_base)
label.set_text("Base")
label.center()
# Create another object with the base style and earnings style too
obj_warning = lv.obj(lv.scr_act())
obj_warning.add_style(style_base, 0)
obj_warning.add_style(style_warning, 0)
obj_warning.align(lv.ALIGN.RIGHT_MID, -20, 0)
label = lv.label(obj_warning)
label.set_text("Warning")
label.center()
Local styles¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Local styles
*/
void lv_example_style_12(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_GREEN));
lv_style_set_border_color(&style, lv_palette_lighten(LV_PALETTE_GREEN, 3));
lv_style_set_border_width(&style, 3);
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj, &style, 0);
/*Overwrite the background color locally*/
lv_obj_set_style_bg_color(obj, lv_palette_main(LV_PALETTE_ORANGE), LV_PART_MAIN);
lv_obj_center(obj);
}
#endif
#
# Local styles
#
style = lv.style_t()
style.init()
style.set_bg_color(lv.palette_main(lv.PALETTE.GREEN))
style.set_border_color(lv.palette_lighten(lv.PALETTE.GREEN, 3))
style.set_border_width(3)
obj = lv.obj(lv.scr_act())
obj.add_style(style, 0)
# Overwrite the background color locally
obj.set_style_bg_color(lv.palette_main(lv.PALETTE.ORANGE), lv.PART.MAIN)
obj.center()
Add styles to parts and states¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
/**
* Add styles to parts and states
*/
void lv_example_style_13(void)
{
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_color(&style_indic, lv_palette_lighten(LV_PALETTE_RED, 3));
lv_style_set_bg_grad_color(&style_indic, lv_palette_main(LV_PALETTE_RED));
lv_style_set_bg_grad_dir(&style_indic, LV_GRAD_DIR_HOR);
static lv_style_t style_indic_pr;
lv_style_init(&style_indic_pr);
lv_style_set_shadow_color(&style_indic_pr, lv_palette_main(LV_PALETTE_RED));
lv_style_set_shadow_width(&style_indic_pr, 10);
lv_style_set_shadow_spread(&style_indic_pr, 3);
/*Create an object with the new style_pr*/
lv_obj_t * obj = lv_slider_create(lv_scr_act());
lv_obj_add_style(obj, &style_indic, LV_PART_INDICATOR);
lv_obj_add_style(obj, &style_indic_pr, LV_PART_INDICATOR | LV_STATE_PRESSED);
lv_slider_set_value(obj, 70, LV_ANIM_OFF);
lv_obj_center(obj);
}
#endif
#
# Add styles to parts and states
#
style_indic = lv.style_t()
style_indic.init()
style_indic.set_bg_color(lv.palette_lighten(lv.PALETTE.RED, 3))
style_indic.set_bg_grad_color(lv.palette_main(lv.PALETTE.RED))
style_indic.set_bg_grad_dir(lv.GRAD_DIR.HOR)
style_indic_pr = lv.style_t()
style_indic_pr.init()
style_indic_pr.set_shadow_color(lv.palette_main(lv.PALETTE.RED))
style_indic_pr.set_shadow_width(10)
style_indic_pr.set_shadow_spread(3)
# Create an object with the new style_pr
obj = lv.slider(lv.scr_act())
obj.add_style(style_indic, lv.PART.INDICATOR)
obj.add_style(style_indic_pr, lv.PART.INDICATOR | lv.STATE.PRESSED)
obj.set_value(70, lv.ANIM.OFF)
obj.center()
Extending the current theme¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMG
static lv_style_t style_btn;
/*Will be called when the styles of the base theme are already added
to add new styles*/
static void new_theme_apply_cb(lv_theme_t * th, lv_obj_t * obj)
{
LV_UNUSED(th);
if(lv_obj_check_type(obj, &lv_btn_class)) {
lv_obj_add_style(obj, &style_btn, 0);
}
}
static void new_theme_init_and_set(void)
{
/*Initialize the styles*/
lv_style_init(&style_btn);
lv_style_set_bg_color(&style_btn, lv_palette_main(LV_PALETTE_GREEN));
lv_style_set_border_color(&style_btn, lv_palette_darken(LV_PALETTE_GREEN, 3));
lv_style_set_border_width(&style_btn, 3);
/*Initialize the new theme from the current theme*/
lv_theme_t * th_act = lv_disp_get_theme(NULL);
static lv_theme_t th_new;
th_new = *th_act;
/*Set the parent theme and the style apply callback for the new theme*/
lv_theme_set_parent(&th_new, th_act);
lv_theme_set_apply_cb(&th_new, new_theme_apply_cb);
/*Assign the new theme to the current display*/
lv_disp_set_theme(NULL, &th_new);
}
/**
* Extending the current theme
*/
void lv_example_style_14(void)
{
lv_obj_t * btn;
lv_obj_t * label;
btn = lv_btn_create(lv_scr_act());
lv_obj_align(btn, LV_ALIGN_TOP_MID, 0, 20);
label = lv_label_create(btn);
lv_label_set_text(label, "Original theme");
new_theme_init_and_set();
btn = lv_btn_create(lv_scr_act());
lv_obj_align(btn, LV_ALIGN_BOTTOM_MID, 0, -20);
label = lv_label_create(btn);
lv_label_set_text(label, "New theme");
}
#endif
# Will be called when the styles of the base theme are already added
# to add new styles
class NewTheme(lv.theme_t):
def __init__(self):
super().__init__()
# Initialize the styles
self.style_btn = lv.style_t()
self.style_btn.init()
self.style_btn.set_bg_color(lv.palette_main(lv.PALETTE.GREEN))
self.style_btn.set_border_color(lv.palette_darken(lv.PALETTE.GREEN, 3))
self.style_btn.set_border_width(3)
# This theme is based on active theme
th_act = lv.theme_get_from_obj(lv.scr_act())
# This theme will be applied only after base theme is applied
self.set_parent(th_act)
class ExampleStyle_14:
def __init__(self):
#
# Extending the current theme
#
btn = lv.btn(lv.scr_act())
btn.align(lv.ALIGN.TOP_MID, 0, 20)
label = lv.label(btn)
label.set_text("Original theme")
self.new_theme_init_and_set()
btn = lv.btn(lv.scr_act())
btn.align(lv.ALIGN.BOTTOM_MID, 0, -20)
label = lv.label(btn)
label.set_text("New theme")
def new_theme_apply_cb(self, th, obj):
print(th,obj)
if obj.get_class() == lv.btn_class:
obj.add_style(self.th_new.style_btn, 0)
def new_theme_init_and_set(self):
print("new_theme_init_and_set")
# Initialize the new theme from the current theme
self.th_new = NewTheme()
self.th_new.set_apply_cb(self.new_theme_apply_cb)
lv.disp_get_default().set_theme(self.th_new)
exampleStyle_14 = ExampleStyle_14()
Opacity and Transformations¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_BTN && LV_USE_LABEL
/**
* Opacity and Transformations
*/
void lv_example_style_15(void)
{
lv_obj_t * btn;
lv_obj_t * label;
/*Normal button*/
btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, 100, 40);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, -70);
label = lv_label_create(btn);
lv_label_set_text(label, "Normal");
lv_obj_center(label);
/*Set opacity
*The button and the label is rendered to a layer first and that layer is blended*/
btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, 100, 40);
lv_obj_set_style_opa(btn, LV_OPA_50, 0);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, 0);
label = lv_label_create(btn);
lv_label_set_text(label, "Opa:50%");
lv_obj_center(label);
/*Set transformations
*The button and the label is rendered to a layer first and that layer is transformed*/
btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, 100, 40);
lv_obj_set_style_transform_angle(btn, 150, 0); /*15 deg*/
lv_obj_set_style_transform_zoom(btn, 256 + 64, 0); /*1.25x*/
lv_obj_set_style_transform_pivot_x(btn, 50, 0);
lv_obj_set_style_transform_pivot_y(btn, 20, 0);
lv_obj_set_style_opa(btn, LV_OPA_50, 0);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, 70);
label = lv_label_create(btn);
lv_label_set_text(label, "Transf.");
lv_obj_center(label);
}
#endif
Error encountered while trying to open /home/runner/work/lvgl/lvgl/examples/styles/lv_example_style_15.py
Animations¶
Start animation on an event¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_x(var, v);
}
static void sw_event_cb(lv_event_t * e)
{
lv_obj_t * sw = lv_event_get_target(e);
lv_obj_t * label = lv_event_get_user_data(e);
if(lv_obj_has_state(sw, LV_STATE_CHECKED)) {
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, label);
lv_anim_set_values(&a, lv_obj_get_x(label), 100);
lv_anim_set_time(&a, 500);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_path_cb(&a, lv_anim_path_overshoot);
lv_anim_start(&a);
}
else {
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, label);
lv_anim_set_values(&a, lv_obj_get_x(label), -lv_obj_get_width(label));
lv_anim_set_time(&a, 500);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_path_cb(&a, lv_anim_path_ease_in);
lv_anim_start(&a);
}
}
/**
* Start animation on an event
*/
void lv_example_anim_1(void)
{
lv_obj_t * label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "Hello animations!");
lv_obj_set_pos(label, 100, 10);
lv_obj_t * sw = lv_switch_create(lv_scr_act());
lv_obj_center(sw);
lv_obj_add_state(sw, LV_STATE_CHECKED);
lv_obj_add_event_cb(sw, sw_event_cb, LV_EVENT_VALUE_CHANGED, label);
}
#endif
def anim_x_cb(label, v):
label.set_x(v)
def sw_event_cb(e,label):
sw = e.get_target()
if sw.has_state(lv.STATE.CHECKED):
a = lv.anim_t()
a.init()
a.set_var(label)
a.set_values(label.get_x(), 100)
a.set_time(500)
a.set_path_cb(lv.anim_t.path_overshoot)
a.set_custom_exec_cb(lambda a,val: anim_x_cb(label,val))
lv.anim_t.start(a)
else:
a = lv.anim_t()
a.init()
a.set_var(label)
a.set_values(label.get_x(), -label.get_width())
a.set_time(500)
a.set_path_cb(lv.anim_t.path_ease_in)
a.set_custom_exec_cb(lambda a,val: anim_x_cb(label,val))
lv.anim_t.start(a)
#
# Start animation on an event
#
label = lv.label(lv.scr_act())
label.set_text("Hello animations!")
label.set_pos(100, 10)
sw = lv.switch(lv.scr_act())
sw.center()
sw.add_state(lv.STATE.CHECKED)
sw.add_event_cb(lambda e: sw_event_cb(e,label), lv.EVENT.VALUE_CHANGED, None)
Playback animation¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_x(var, v);
}
static void anim_size_cb(void * var, int32_t v)
{
lv_obj_set_size(var, v, v);
}
/**
* Create a playback animation
*/
void lv_example_anim_2(void)
{
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_set_style_bg_color(obj, lv_palette_main(LV_PALETTE_RED), 0);
lv_obj_set_style_radius(obj, LV_RADIUS_CIRCLE, 0);
lv_obj_align(obj, LV_ALIGN_LEFT_MID, 10, 0);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, obj);
lv_anim_set_values(&a, 10, 50);
lv_anim_set_time(&a, 1000);
lv_anim_set_playback_delay(&a, 100);
lv_anim_set_playback_time(&a, 300);
lv_anim_set_repeat_delay(&a, 500);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_path_cb(&a, lv_anim_path_ease_in_out);
lv_anim_set_exec_cb(&a, anim_size_cb);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_values(&a, 10, 240);
lv_anim_start(&a);
}
#endif
def anim_x_cb(obj, v):
obj.set_x(v)
def anim_size_cb(obj, v):
obj.set_size(v, v)
#
# Create a playback animation
#
obj = lv.obj(lv.scr_act())
obj.set_style_bg_color(lv.palette_main(lv.PALETTE.RED), 0)
obj.set_style_radius(lv.RADIUS.CIRCLE, 0)
obj.align(lv.ALIGN.LEFT_MID, 10, 0)
a1 = lv.anim_t()
a1.init()
a1.set_var(obj)
a1.set_values(10, 50)
a1.set_time(1000)
a1.set_playback_delay(100)
a1.set_playback_time(300)
a1.set_repeat_delay(500)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a1.set_path_cb(lv.anim_t.path_ease_in_out)
a1.set_custom_exec_cb(lambda a1,val: anim_size_cb(obj,val))
lv.anim_t.start(a1)
a2 = lv.anim_t()
a2.init()
a2.set_var(obj)
a2.set_values(10, 240)
a2.set_time(1000)
a2.set_playback_delay(100)
a2.set_playback_time(300)
a2.set_repeat_delay(500)
a2.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a2.set_path_cb(lv.anim_t.path_ease_in_out)
a2.set_custom_exec_cb(lambda a1,val: anim_x_cb(obj,val))
lv.anim_t.start(a2)
Animation timeline¶
C code
GitHub#include "../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
static lv_anim_timeline_t * anim_timeline = NULL;
static lv_obj_t * obj1 = NULL;
static lv_obj_t * obj2 = NULL;
static lv_obj_t * obj3 = NULL;
static const lv_coord_t obj_width = 90;
static const lv_coord_t obj_height = 70;
static void set_width(void * var, int32_t v)
{
lv_obj_set_width((lv_obj_t *)var, v);
}
static void set_height(void * var, int32_t v)
{
lv_obj_set_height((lv_obj_t *)var, v);
}
static void anim_timeline_create(void)
{
/* obj1 */
lv_anim_t a1;
lv_anim_init(&a1);
lv_anim_set_var(&a1, obj1);
lv_anim_set_values(&a1, 0, obj_width);
lv_anim_set_early_apply(&a1, false);
lv_anim_set_exec_cb(&a1, (lv_anim_exec_xcb_t)set_width);
lv_anim_set_path_cb(&a1, lv_anim_path_overshoot);
lv_anim_set_time(&a1, 300);
lv_anim_t a2;
lv_anim_init(&a2);
lv_anim_set_var(&a2, obj1);
lv_anim_set_values(&a2, 0, obj_height);
lv_anim_set_early_apply(&a2, false);
lv_anim_set_exec_cb(&a2, (lv_anim_exec_xcb_t)set_height);
lv_anim_set_path_cb(&a2, lv_anim_path_ease_out);
lv_anim_set_time(&a2, 300);
/* obj2 */
lv_anim_t a3;
lv_anim_init(&a3);
lv_anim_set_var(&a3, obj2);
lv_anim_set_values(&a3, 0, obj_width);
lv_anim_set_early_apply(&a3, false);
lv_anim_set_exec_cb(&a3, (lv_anim_exec_xcb_t)set_width);
lv_anim_set_path_cb(&a3, lv_anim_path_overshoot);
lv_anim_set_time(&a3, 300);
lv_anim_t a4;
lv_anim_init(&a4);
lv_anim_set_var(&a4, obj2);
lv_anim_set_values(&a4, 0, obj_height);
lv_anim_set_early_apply(&a4, false);
lv_anim_set_exec_cb(&a4, (lv_anim_exec_xcb_t)set_height);
lv_anim_set_path_cb(&a4, lv_anim_path_ease_out);
lv_anim_set_time(&a4, 300);
/* obj3 */
lv_anim_t a5;
lv_anim_init(&a5);
lv_anim_set_var(&a5, obj3);
lv_anim_set_values(&a5, 0, obj_width);
lv_anim_set_early_apply(&a5, false);
lv_anim_set_exec_cb(&a5, (lv_anim_exec_xcb_t)set_width);
lv_anim_set_path_cb(&a5, lv_anim_path_overshoot);
lv_anim_set_time(&a5, 300);
lv_anim_t a6;
lv_anim_init(&a6);
lv_anim_set_var(&a6, obj3);
lv_anim_set_values(&a6, 0, obj_height);
lv_anim_set_early_apply(&a6, false);
lv_anim_set_exec_cb(&a6, (lv_anim_exec_xcb_t)set_height);
lv_anim_set_path_cb(&a6, lv_anim_path_ease_out);
lv_anim_set_time(&a6, 300);
/* Create anim timeline */
anim_timeline = lv_anim_timeline_create();
lv_anim_timeline_add(anim_timeline, 0, &a1);
lv_anim_timeline_add(anim_timeline, 0, &a2);
lv_anim_timeline_add(anim_timeline, 200, &a3);
lv_anim_timeline_add(anim_timeline, 200, &a4);
lv_anim_timeline_add(anim_timeline, 400, &a5);
lv_anim_timeline_add(anim_timeline, 400, &a6);
}
static void btn_start_event_handler(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_target(e);
if(!anim_timeline) {
anim_timeline_create();
}
bool reverse = lv_obj_has_state(btn, LV_STATE_CHECKED);
lv_anim_timeline_set_reverse(anim_timeline, reverse);
lv_anim_timeline_start(anim_timeline);
}
static void btn_del_event_handler(lv_event_t * e)
{
LV_UNUSED(e);
if(anim_timeline) {
lv_anim_timeline_del(anim_timeline);
anim_timeline = NULL;
}
}
static void btn_stop_event_handler(lv_event_t * e)
{
LV_UNUSED(e);
if(anim_timeline) {
lv_anim_timeline_stop(anim_timeline);
}
}
static void slider_prg_event_handler(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
if(!anim_timeline) {
anim_timeline_create();
}
int32_t progress = lv_slider_get_value(slider);
lv_anim_timeline_set_progress(anim_timeline, progress);
}
/**
* Create an animation timeline
*/
void lv_example_anim_timeline_1(void)
{
lv_obj_t * par = lv_scr_act();
lv_obj_set_flex_flow(par, LV_FLEX_FLOW_ROW);
lv_obj_set_flex_align(par, LV_FLEX_ALIGN_SPACE_AROUND, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
/* create btn_start */
lv_obj_t * btn_start = lv_btn_create(par);
lv_obj_add_event_cb(btn_start, btn_start_event_handler, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_add_flag(btn_start, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_add_flag(btn_start, LV_OBJ_FLAG_CHECKABLE);
lv_obj_align(btn_start, LV_ALIGN_TOP_MID, -100, 20);
lv_obj_t * label_start = lv_label_create(btn_start);
lv_label_set_text(label_start, "Start");
lv_obj_center(label_start);
/* create btn_del */
lv_obj_t * btn_del = lv_btn_create(par);
lv_obj_add_event_cb(btn_del, btn_del_event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_add_flag(btn_del, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(btn_del, LV_ALIGN_TOP_MID, 0, 20);
lv_obj_t * label_del = lv_label_create(btn_del);
lv_label_set_text(label_del, "Delete");
lv_obj_center(label_del);
/* create btn_stop */
lv_obj_t * btn_stop = lv_btn_create(par);
lv_obj_add_event_cb(btn_stop, btn_stop_event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_add_flag(btn_stop, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(btn_stop, LV_ALIGN_TOP_MID, 100, 20);
lv_obj_t * label_stop = lv_label_create(btn_stop);
lv_label_set_text(label_stop, "Stop");
lv_obj_center(label_stop);
/* create slider_prg */
lv_obj_t * slider_prg = lv_slider_create(par);
lv_obj_add_event_cb(slider_prg, slider_prg_event_handler, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_add_flag(slider_prg, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(slider_prg, LV_ALIGN_BOTTOM_MID, 0, -20);
lv_slider_set_range(slider_prg, 0, 65535);
/* create 3 objects */
obj1 = lv_obj_create(par);
lv_obj_set_size(obj1, obj_width, obj_height);
obj2 = lv_obj_create(par);
lv_obj_set_size(obj2, obj_width, obj_height);
obj3 = lv_obj_create(par);
lv_obj_set_size(obj3, obj_width, obj_height);
}
#endif
class LV_ExampleAnimTimeline_1(object):
def __init__(self):
self.obj_width = 120
self.obj_height = 150
#
# Create an animation timeline
#
self.par = lv.scr_act()
self.par.set_flex_flow(lv.FLEX_FLOW.ROW)
self.par.set_flex_align(lv.FLEX_ALIGN.SPACE_AROUND, lv.FLEX_ALIGN.CENTER, lv.FLEX_ALIGN.CENTER)
self.btn_run = lv.btn(self.par)
self.btn_run.add_event_cb(self.btn_run_event_handler, lv.EVENT.VALUE_CHANGED, None)
self.btn_run.add_flag(lv.obj.FLAG.IGNORE_LAYOUT)
self.btn_run.add_flag(lv.obj.FLAG.CHECKABLE)
self.btn_run.align(lv.ALIGN.TOP_MID, -50, 20)
self.label_run = lv.label(self.btn_run)
self.label_run.set_text("Run")
self.label_run.center()
self.btn_del = lv.btn(self.par)
self.btn_del.add_event_cb(self.btn_del_event_handler, lv.EVENT.CLICKED, None)
self.btn_del.add_flag(lv.obj.FLAG.IGNORE_LAYOUT)
self.btn_del.align(lv.ALIGN.TOP_MID, 50, 20)
self.label_del = lv.label(self.btn_del)
self.label_del.set_text("Stop")
self.label_del.center()
self.slider = lv.slider(self.par)
self.slider.add_event_cb(self.slider_prg_event_handler, lv.EVENT.VALUE_CHANGED, None)
self.slider.add_flag(lv.obj.FLAG.IGNORE_LAYOUT)
self.slider.align(lv.ALIGN.BOTTOM_RIGHT, -20, -20)
self.slider.set_range(0, 65535)
self.obj1 = lv.obj(self.par)
self.obj1.set_size(self.obj_width, self.obj_height)
self.obj2 = lv.obj(self.par)
self.obj2.set_size(self.obj_width, self.obj_height)
self.obj3 = lv.obj(self.par)
self.obj3.set_size(self.obj_width, self.obj_height)
self.anim_timeline = None
def set_width(self,obj, v):
obj.set_width(v)
def set_height(self,obj, v):
obj.set_height(v)
def anim_timeline_create(self):
# obj1
self.a1 = lv.anim_t()
self.a1.init()
self.a1.set_values(0, self.obj_width)
self.a1.set_early_apply(False)
self.a1.set_custom_exec_cb(lambda a,v: self.set_width(self.obj1,v))
self.a1.set_path_cb(lv.anim_t.path_overshoot)
self.a1.set_time(300)
self.a2 = lv.anim_t()
self.a2.init()
self.a2.set_values(0, self.obj_height)
self.a2.set_early_apply(False)
self.a2.set_custom_exec_cb(lambda a,v: self.set_height(self.obj1,v))
self.a2.set_path_cb(lv.anim_t.path_ease_out)
self.a2.set_time(300)
# obj2
self.a3=lv.anim_t()
self.a3.init()
self.a3.set_values(0, self.obj_width)
self.a3.set_early_apply(False)
self.a3.set_custom_exec_cb(lambda a,v: self.set_width(self.obj2,v))
self.a3.set_path_cb(lv.anim_t.path_overshoot)
self.a3.set_time(300)
self.a4 = lv.anim_t()
self.a4.init()
self.a4.set_values(0, self.obj_height)
self.a4.set_early_apply(False)
self.a4.set_custom_exec_cb(lambda a,v: self.set_height(self.obj2,v))
self.a4.set_path_cb(lv.anim_t.path_ease_out)
self.a4.set_time(300)
# obj3
self.a5 = lv.anim_t()
self.a5.init()
self.a5.set_values(0, self.obj_width)
self.a5.set_early_apply(False)
self.a5.set_custom_exec_cb(lambda a,v: self.set_width(self.obj3,v))
self.a5.set_path_cb(lv.anim_t.path_overshoot)
self.a5.set_time(300)
self.a6 = lv.anim_t()
self.a6.init()
self.a6.set_values(0, self.obj_height)
self.a6.set_early_apply(False)
self.a6.set_custom_exec_cb(lambda a,v: self.set_height(self.obj3,v))
self.a6.set_path_cb(lv.anim_t.path_ease_out)
self.a6.set_time(300)
# Create anim timeline
print("Create new anim_timeline")
self.anim_timeline = lv.anim_timeline_create()
lv.anim_timeline_add(self.anim_timeline, 0, self.a1)
lv.anim_timeline_add(self.anim_timeline, 0, self.a2)
lv.anim_timeline_add(self.anim_timeline, 200, self.a3)
lv.anim_timeline_add(self.anim_timeline, 200, self.a4)
lv.anim_timeline_add(self.anim_timeline, 400, self.a5)
lv.anim_timeline_add(self.anim_timeline, 400, self.a6)
def slider_prg_event_handler(self,e):
slider = e.get_target()
if not self.anim_timeline:
self.anim_timeline_create()
progress = slider.get_value()
lv.anim_timeline_set_progress(self.anim_timeline, progress)
def btn_run_event_handler(self,e):
btn = e.get_target()
if not self.anim_timeline:
self.anim_timeline_create()
reverse = btn.has_state(lv.STATE.CHECKED)
lv.anim_timeline_set_reverse(self.anim_timeline,reverse)
lv.anim_timeline_start(self.anim_timeline)
def btn_del_event_handler(self,e):
if self.anim_timeline:
lv.anim_timeline_del(self.anim_timeline)
self.anim_timeline = None
lv_example_anim_timeline_1 = LV_ExampleAnimTimeline_1()
Events¶
Button click event¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void event_cb(lv_event_t * e)
{
LV_LOG_USER("Clicked");
static uint32_t cnt = 1;
lv_obj_t * btn = lv_event_get_target(e);
lv_obj_t * label = lv_obj_get_child(btn, 0);
lv_label_set_text_fmt(label, "%"LV_PRIu32, cnt);
cnt++;
}
/**
* Add click event to a button
*/
void lv_example_event_1(void)
{
lv_obj_t * btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, 100, 50);
lv_obj_center(btn);
lv_obj_add_event_cb(btn, event_cb, LV_EVENT_CLICKED, NULL);
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text(label, "Click me!");
lv_obj_center(label);
}
#endif
class Event_1():
def __init__(self):
self.cnt = 1
#
# Add click event to a button
#
btn = lv.btn(lv.scr_act())
btn.set_size(100, 50)
btn.center()
btn.add_event_cb(self.event_cb, lv.EVENT.CLICKED, None)
label = lv.label(btn)
label.set_text("Click me!")
label.center()
def event_cb(self,e):
print("Clicked")
btn = e.get_target()
label = btn.get_child(0)
label.set_text(str(self.cnt))
self.cnt += 1
evt1 = Event_1()
Handle multiple events¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * label = lv_event_get_user_data(e);
switch(code) {
case LV_EVENT_PRESSED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_PRESSED");
break;
case LV_EVENT_CLICKED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_CLICKED");
break;
case LV_EVENT_LONG_PRESSED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_LONG_PRESSED");
break;
case LV_EVENT_LONG_PRESSED_REPEAT:
lv_label_set_text(label, "The last button event:\nLV_EVENT_LONG_PRESSED_REPEAT");
break;
default:
break;
}
}
/**
* Handle multiple events
*/
void lv_example_event_2(void)
{
lv_obj_t * btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, 100, 50);
lv_obj_center(btn);
lv_obj_t * btn_label = lv_label_create(btn);
lv_label_set_text(btn_label, "Click me!");
lv_obj_center(btn_label);
lv_obj_t * info_label = lv_label_create(lv_scr_act());
lv_label_set_text(info_label, "The last button event:\nNone");
lv_obj_add_event_cb(btn, event_cb, LV_EVENT_ALL, info_label);
}
#endif
def event_cb(e,label):
code = e.get_code()
if code == lv.EVENT.PRESSED:
label.set_text("The last button event:\nLV_EVENT_PRESSED")
elif code == lv.EVENT.CLICKED:
label.set_text("The last button event:\nLV_EVENT_CLICKED")
elif code == lv.EVENT.LONG_PRESSED:
label.set_text("The last button event:\nLV_EVENT_LONG_PRESSED")
elif code == lv.EVENT.LONG_PRESSED_REPEAT:
label.set_text("The last button event:\nLV_EVENT_LONG_PRESSED_REPEAT")
btn = lv.btn(lv.scr_act())
btn.set_size(100, 50)
btn.center()
btn_label = lv.label(btn)
btn_label.set_text("Click me!")
btn_label.center()
info_label = lv.label(lv.scr_act())
info_label.set_text("The last button event:\nNone")
btn.add_event_cb(lambda e: event_cb(e,info_label), lv.EVENT.ALL, None)
Event bubbling¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void event_cb(lv_event_t * e)
{
/*The original target of the event. Can be the buttons or the container*/
lv_obj_t * target = lv_event_get_target(e);
/*The current target is always the container as the event is added to it*/
lv_obj_t * cont = lv_event_get_current_target(e);
/*If container was clicked do nothing*/
if(target == cont) return;
/*Make the clicked buttons red*/
lv_obj_set_style_bg_color(target, lv_palette_main(LV_PALETTE_RED), 0);
}
/**
* Demonstrate event bubbling
*/
void lv_example_event_3(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 290, 200);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 30; i++) {
lv_obj_t * btn = lv_btn_create(cont);
lv_obj_set_size(btn, 80, 50);
lv_obj_add_flag(btn, LV_OBJ_FLAG_EVENT_BUBBLE);
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
lv_obj_add_event_cb(cont, event_cb, LV_EVENT_CLICKED, NULL);
}
#endif
def event_cb(e):
# The original target of the event. Can be the buttons or the container
target = e.get_target()
# print(type(target))
# If container was clicked do nothing
if type(target) != type(lv.btn()):
return
# Make the clicked buttons red
target.set_style_bg_color(lv.palette_main(lv.PALETTE.RED), 0)
#
# Demonstrate event bubbling
#
cont = lv.obj(lv.scr_act())
cont.set_size(320, 200)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
for i in range(30):
btn = lv.btn(cont)
btn.set_size(80, 50)
btn.add_flag(lv.obj.FLAG.EVENT_BUBBLE)
label = lv.label(btn)
label.set_text(str(i))
label.center()
cont.add_event_cb(event_cb, lv.EVENT.CLICKED, None)
Layouts¶
Flex¶
A simple row and a column layout with flexbox¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* A simple row and a column layout with flexbox
*/
void lv_example_flex_1(void)
{
/*Create a container with ROW flex direction*/
lv_obj_t * cont_row = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont_row, 300, 75);
lv_obj_align(cont_row, LV_ALIGN_TOP_MID, 0, 5);
lv_obj_set_flex_flow(cont_row, LV_FLEX_FLOW_ROW);
/*Create a container with COLUMN flex direction*/
lv_obj_t * cont_col = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont_col, 200, 150);
lv_obj_align_to(cont_col, cont_row, LV_ALIGN_OUT_BOTTOM_MID, 0, 5);
lv_obj_set_flex_flow(cont_col, LV_FLEX_FLOW_COLUMN);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_obj_t * obj;
lv_obj_t * label;
/*Add items to the row*/
obj = lv_btn_create(cont_row);
lv_obj_set_size(obj, 100, LV_PCT(100));
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32, i);
lv_obj_center(label);
/*Add items to the column*/
obj = lv_btn_create(cont_col);
lv_obj_set_size(obj, LV_PCT(100), LV_SIZE_CONTENT);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
#
# A simple row and a column layout with flexbox
#
# Create a container with ROW flex direction
cont_row = lv.obj(lv.scr_act())
cont_row.set_size(300, 75)
cont_row.align(lv.ALIGN.TOP_MID, 0, 5)
cont_row.set_flex_flow(lv.FLEX_FLOW.ROW)
# Create a container with COLUMN flex direction
cont_col = lv.obj(lv.scr_act())
cont_col.set_size(200, 150)
cont_col.align_to(cont_row, lv.ALIGN.OUT_BOTTOM_MID, 0, 5)
cont_col.set_flex_flow(lv.FLEX_FLOW.COLUMN)
for i in range(10):
# Add items to the row
obj = lv.btn(cont_row)
obj.set_size(100, lv.pct(100))
label = lv.label(obj)
label.set_text("Item: {:d}".format(i))
label.center()
# Add items to the column
obj = lv.btn(cont_col)
obj.set_size(lv.pct(100), lv.SIZE.CONTENT)
label = lv.label(obj)
label.set_text("Item: {:d}".format(i))
label.center()
Arrange items in rows with wrap and even spacing¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Arrange items in rows with wrap and place the items to get even space around them.
*/
void lv_example_flex_2(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_flex_flow(&style, LV_FLEX_FLOW_ROW_WRAP);
lv_style_set_flex_main_place(&style, LV_FLEX_ALIGN_SPACE_EVENLY);
lv_style_set_layout(&style, LV_LAYOUT_FLEX);
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_add_style(cont, &style, 0);
uint32_t i;
for(i = 0; i < 8; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_add_flag(obj, LV_OBJ_FLAG_CHECKABLE);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
#
# Arrange items in rows with wrap and place the items to get even space around them.
#
style = lv.style_t()
style.init()
style.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
style.set_flex_main_place(lv.FLEX_ALIGN.SPACE_EVENLY)
style.set_layout(lv.LAYOUT_FLEX.value)
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.add_style(style, 0)
for i in range(8):
obj = lv.obj(cont)
obj.set_size(70, lv.SIZE.CONTENT)
label = lv.label(obj)
label.set_text("{:d}".format(i))
label.center()
Demonstrate flex grow¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Demonstrate flex grow.
*/
void lv_example_flex_3(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW);
lv_obj_t * obj;
obj = lv_obj_create(cont);
lv_obj_set_size(obj, 40, 40); /*Fix size*/
obj = lv_obj_create(cont);
lv_obj_set_height(obj, 40);
lv_obj_set_flex_grow(obj, 1); /*1 portion from the free space*/
obj = lv_obj_create(cont);
lv_obj_set_height(obj, 40);
lv_obj_set_flex_grow(obj, 2); /*2 portion from the free space*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, 40, 40); /*Fix size. It is flushed to the right by the "grow" items*/
}
#endif
#
# Demonstrate flex grow.
#
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.ROW)
obj = lv.obj(cont)
obj.set_size(40, 40) # Fix size
obj = lv.obj(cont)
obj.set_height(40)
obj.set_flex_grow(1) # 1 portion from the free space
obj = lv.obj(cont)
obj.set_height(40)
obj.set_flex_grow(2) # 2 portion from the free space
obj = lv.obj(cont)
obj.set_size(40, 40) # Fix size. It is flushed to the right by the "grow" items
Demonstrate flex grow.¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Reverse the order of flex items
*/
void lv_example_flex_4(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_COLUMN_REVERSE);
uint32_t i;
for(i = 0; i < 6; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 100, 50);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
#
# Reverse the order of flex items
#
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.COLUMN_REVERSE)
for i in range(6):
obj = lv.obj(cont)
obj.set_size(100, 50)
label = lv.label(obj)
label.set_text("Item: " + str(i))
label.center()
Demonstrate column and row gap style properties¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
static void row_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_row(obj, v, 0);
}
static void column_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_column(obj, v, 0);
}
/**
* Demonstrate the effect of column and row gap style properties
*/
void lv_example_flex_5(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 9; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, cont);
lv_anim_set_values(&a, 0, 10);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_exec_cb(&a, row_gap_anim);
lv_anim_set_time(&a, 500);
lv_anim_set_playback_time(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_time(&a, 3000);
lv_anim_set_playback_time(&a, 3000);
lv_anim_start(&a);
}
#endif
def row_gap_anim(obj, v):
obj.set_style_pad_row(v, 0)
def column_gap_anim(obj, v):
obj.set_style_pad_column(v, 0)
#
# Demonstrate the effect of column and row gap style properties
#
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
for i in range(9):
obj = lv.obj(cont)
obj.set_size(70, lv.SIZE.CONTENT)
label = lv.label(obj)
label.set_text(str(i))
label.center()
a_row = lv.anim_t()
a_row.init()
a_row.set_var(cont)
a_row.set_values(0, 10)
a_row.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a_row.set_time(500)
a_row.set_playback_time(500)
a_row.set_custom_exec_cb(lambda a,val: row_gap_anim(cont,val))
lv.anim_t.start(a_row)
a_col = lv.anim_t()
a_col.init()
a_col.set_var(cont)
a_col.set_values(0, 10)
a_col.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a_col.set_time(3000)
a_col.set_playback_time(3000)
a_col.set_custom_exec_cb(lambda a,val: column_gap_anim(cont,val))
lv.anim_t.start(a_col)
RTL base direction changes order of the items¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* RTL base direction changes order of the items.
* Also demonstrate how horizontal scrolling works with RTL.
*/
void lv_example_flex_6(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_style_base_dir(cont, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 20; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
#
# RTL base direction changes order of the items.
# Also demonstrate how horizontal scrolling works with RTL.
#
cont = lv.obj(lv.scr_act())
cont.set_style_base_dir(lv.BASE_DIR.RTL,0)
cont.set_size(300, 220)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
for i in range(20):
obj = lv.obj(cont)
obj.set_size(70, lv.SIZE.CONTENT)
label = lv.label(obj)
label.set_text(str(i))
label.center()
Grid¶
A simple grid¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* A simple grid
*/
void lv_example_grid_1(void)
{
static lv_coord_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static lv_coord_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_style_grid_column_dsc_array(cont, col_dsc, 0);
lv_obj_set_style_grid_row_dsc_array(cont, row_dsc, 0);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_layout(cont, LV_LAYOUT_GRID);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_btn_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "c%d, r%d", col, row);
lv_obj_center(label);
}
}
#endif
#
# A simple grid
#
col_dsc = [70, 70, 70, lv.GRID_TEMPLATE.LAST]
row_dsc = [50, 50, 50, lv.GRID_TEMPLATE.LAST]
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_style_grid_column_dsc_array(col_dsc, 0)
cont.set_style_grid_row_dsc_array(row_dsc, 0)
cont.set_size(300, 220)
cont.center()
cont.set_layout(lv.LAYOUT_GRID.value)
for i in range(9):
col = i % 3
row = i // 3
obj = lv.btn(cont)
# Stretch the cell horizontally and vertically too
# Set span to 1 to make the cell 1 column/row sized
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, col, 1,
lv.GRID_ALIGN.STRETCH, row, 1)
label = lv.label(obj)
label.set_text("c" +str(col) + "r" +str(row))
label.center()
Demonstrate cell placement and span¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate cell placement and span
*/
void lv_example_grid_2(void)
{
static lv_coord_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static lv_coord_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_t * label;
lv_obj_t * obj;
/*Cell to 0;0 and align to to the start (left/top) horizontally and vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 0, 1,
LV_GRID_ALIGN_START, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c0, r0");
/*Cell to 1;0 and align to to the start (left) horizontally and center vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 1, 1,
LV_GRID_ALIGN_CENTER, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c1, r0");
/*Cell to 2;0 and align to to the start (left) horizontally and end (bottom) vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 2, 1,
LV_GRID_ALIGN_END, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c2, r0");
/*Cell to 1;1 but 2 column wide (span = 2).Set width and height to stretched.*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, 1, 2,
LV_GRID_ALIGN_STRETCH, 1, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c1-2, r1");
/*Cell to 0;1 but 2 rows tall (span = 2).Set width and height to stretched.*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, 0, 1,
LV_GRID_ALIGN_STRETCH, 1, 2);
label = lv_label_create(obj);
lv_label_set_text(label, "c0\nr1-2");
}
#endif
#
# Demonstrate cell placement and span
#
col_dsc = [70, 70, 70, lv.GRID_TEMPLATE.LAST]
row_dsc = [50, 50, 50, lv.GRID_TEMPLATE.LAST]
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_grid_dsc_array(col_dsc, row_dsc)
cont.set_size(300, 220)
cont.center()
# Cell to 0;0 and align to the start (left/top) horizontally and vertically too
obj = lv.obj(cont)
obj.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
obj.set_grid_cell(lv.GRID_ALIGN.START, 0, 1,
lv.GRID_ALIGN.START, 0, 1)
label = lv.label(obj)
label.set_text("c0, r0")
# Cell to 1;0 and align to the start (left) horizontally and center vertically too
obj = lv.obj(cont)
obj.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
obj.set_grid_cell(lv.GRID_ALIGN.START, 1, 1,
lv.GRID_ALIGN.CENTER, 0, 1)
label = lv.label(obj)
label.set_text("c1, r0")
# Cell to 2;0 and align to the start (left) horizontally and end (bottom) vertically too
obj = lv.obj(cont)
obj.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
obj.set_grid_cell(lv.GRID_ALIGN.START, 2, 1,
lv.GRID_ALIGN.END, 0, 1)
label = lv.label(obj)
label.set_text("c2, r0")
# Cell to 1;1 but 2 column wide (span = 2).Set width and height to stretched.
obj = lv.obj(cont)
obj.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, 1, 2,
lv.GRID_ALIGN.STRETCH, 1, 1)
label = lv.label(obj)
label.set_text("c1-2, r1")
# Cell to 0;1 but 2 rows tall (span = 2).Set width and height to stretched.
obj = lv.obj(cont)
obj.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, 0, 1,
lv.GRID_ALIGN.STRETCH, 1, 2)
label = lv.label(obj)
label.set_text("c0\nr1-2")
Demonstrate grid's "free unit"¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate grid's "free unit"
*/
void lv_example_grid_3(void)
{
/*Column 1: fix width 60 px
*Column 2: 1 unit from the remaining free space
*Column 3: 2 unit from the remaining free space*/
static lv_coord_t col_dsc[] = {60, LV_GRID_FR(1), LV_GRID_FR(2), LV_GRID_TEMPLATE_LAST};
/*Row 1: fix width 50 px
*Row 2: 1 unit from the remaining free space
*Row 3: fix width 50 px*/
static lv_coord_t row_dsc[] = {50, LV_GRID_FR(1), 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
#
# Demonstrate grid's "free unit"
#
# Column 1: fix width 60 px
# Column 2: 1 unit from the remaining free space
# Column 3: 2 unit from the remaining free space
col_dsc = [60, lv.grid_fr(1), lv.grid_fr(2), lv.GRID_TEMPLATE.LAST]
# Row 1: fix width 60 px
# Row 2: 1 unit from the remaining free space
# Row 3: fix width 60 px
row_dsc = [40, lv.grid_fr(1), 40, lv.GRID_TEMPLATE.LAST]
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_grid_dsc_array(col_dsc, row_dsc)
for i in range(9):
col = i % 3
row = i // 3
obj = lv.obj(cont)
# Stretch the cell horizontally and vertically too
# Set span to 1 to make the cell 1 column/row sized
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, col, 1,
lv.GRID_ALIGN.STRETCH, row, 1)
label = lv.label(obj)
label.set_text("%d,%d"%(col, row))
label.center()
Demonstrate track placement¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate track placement
*/
void lv_example_grid_4(void)
{
static lv_coord_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static lv_coord_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Add space between the columns and move the rows to the bottom (end)*/
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_grid_align(cont, LV_GRID_ALIGN_SPACE_BETWEEN, LV_GRID_ALIGN_END);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
#
# Demonstrate track placement
#
col_dsc = [60, 60, 60, lv.GRID_TEMPLATE.LAST]
row_dsc = [40, 40, 40, lv.GRID_TEMPLATE.LAST]
# Add space between the columns and move the rows to the bottom (end)
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_grid_align(lv.GRID_ALIGN.SPACE_BETWEEN, lv.GRID_ALIGN.END)
cont.set_grid_dsc_array(col_dsc, row_dsc)
cont.set_size(300, 220)
cont.center()
for i in range(9):
col = i % 3
row = i // 3
obj = lv.obj(cont)
# Stretch the cell horizontally and vertically too
# Set span to 1 to make the cell 1 column/row sized
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, col, 1,
lv.GRID_ALIGN.STRETCH, row, 1)
label = lv.label(obj)
label.set_text("{:d}{:d}".format(col, row))
label.center()
Demonstrate column and row gap¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
static void row_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_row(obj, v, 0);
}
static void column_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_column(obj, v, 0);
}
/**
* Demonstrate column and row gap
*/
void lv_example_grid_5(void)
{
/*60x60 cells*/
static lv_coord_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static lv_coord_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, cont);
lv_anim_set_values(&a, 0, 10);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_exec_cb(&a, row_gap_anim);
lv_anim_set_time(&a, 500);
lv_anim_set_playback_time(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_time(&a, 3000);
lv_anim_set_playback_time(&a, 3000);
lv_anim_start(&a);
}
#endif
def row_gap_anim(obj, v):
obj.set_style_pad_row(v, 0)
def column_gap_anim(obj, v):
obj.set_style_pad_column(v, 0)
#
# Demonstrate column and row gap
#
# 60x60 cells
col_dsc = [60, 60, 60, lv.GRID_TEMPLATE.LAST]
row_dsc = [40, 40, 40, lv.GRID_TEMPLATE.LAST]
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_grid_dsc_array(col_dsc, row_dsc)
for i in range(9):
col = i % 3
row = i // 3
obj = lv.obj(cont)
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, col, 1,
lv.GRID_ALIGN.STRETCH, row, 1)
label = lv.label(obj)
label.set_text("{:d},{:d}".format(col, row))
label.center()
a_row = lv.anim_t()
a_row.init()
a_row.set_var(cont)
a_row.set_values(0, 10)
a_row.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a_row.set_time(500)
a_row.set_playback_time(500)
a_row. set_custom_exec_cb(lambda a,val: row_gap_anim(cont,val))
lv.anim_t.start(a_row)
a_col = lv.anim_t()
a_col.init()
a_col.set_var(cont)
a_col.set_values(0, 10)
a_col.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a_col.set_time(500)
a_col.set_playback_time(500)
a_col. set_custom_exec_cb(lambda a,val: column_gap_anim(cont,val))
lv.anim_t.start(a_col)
Demonstrate RTL direction on grid¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate RTL direction on grid
*/
void lv_example_grid_6(void)
{
static lv_coord_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static lv_coord_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_style_base_dir(cont, LV_BASE_DIR_RTL, 0);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
#
# Demonstrate RTL direction on grid
#
col_dsc = [60, 60, 60, lv.GRID_TEMPLATE.LAST]
row_dsc = [40, 40, 40, lv.GRID_TEMPLATE.LAST]
# Create a container with grid
cont = lv.obj(lv.scr_act())
cont.set_size(300, 220)
cont.center()
cont.set_style_base_dir(lv.BASE_DIR.RTL,0)
cont.set_grid_dsc_array(col_dsc, row_dsc)
for i in range(9):
col = i % 3
row = i // 3
obj = lv.obj(cont)
# Stretch the cell horizontally and vertically too
# Set span to 1 to make the cell 1 column/row sized
obj.set_grid_cell(lv.GRID_ALIGN.STRETCH, col, 1,
lv.GRID_ALIGN.STRETCH, row, 1)
label = lv.label(obj)
label.set_text("{:d},{:d}".format(col, row))
label.center()
Scrolling¶
Nested scrolling¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Demonstrate how scrolling appears automatically
*/
void lv_example_scroll_1(void)
{
/*Create an object with the new style*/
lv_obj_t * panel = lv_obj_create(lv_scr_act());
lv_obj_set_size(panel, 200, 200);
lv_obj_center(panel);
lv_obj_t * child;
lv_obj_t * label;
child = lv_obj_create(panel);
lv_obj_set_pos(child, 0, 0);
lv_obj_set_size(child, 70, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Zero");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 160, 80);
lv_obj_set_size(child, 80, 80);
lv_obj_t * child2 = lv_btn_create(child);
lv_obj_set_size(child2, 100, 50);
label = lv_label_create(child2);
lv_label_set_text(label, "Right");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 40, 160);
lv_obj_set_size(child, 100, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Bottom");
lv_obj_center(label);
}
#endif
#
# Demonstrate how scrolling appears automatically
#
# Create an object with the new style
panel = lv.obj(lv.scr_act())
panel.set_size(200, 200)
panel.center()
child = lv.obj(panel)
child.set_pos(0, 0)
label = lv.label(child)
label.set_text("Zero")
label.center()
child = lv.obj(panel)
child.set_pos(-40, 100)
label = lv.label(child)
label.set_text("Left")
label.center()
child = lv.obj(panel)
child.set_pos(90, -30)
label = lv.label(child)
label.set_text("Top")
label.center()
child = lv.obj(panel)
child.set_pos(150, 80)
label = lv.label(child)
label.set_text("Right")
label.center()
child = lv.obj(panel)
child.set_pos(60, 170)
label = lv.label(child)
label.set_text("Bottom")
label.center()
Snapping¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void sw_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * sw = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_obj_t * list = lv_event_get_user_data(e);
if(lv_obj_has_state(sw, LV_STATE_CHECKED)) lv_obj_add_flag(list, LV_OBJ_FLAG_SCROLL_ONE);
else lv_obj_clear_flag(list, LV_OBJ_FLAG_SCROLL_ONE);
}
}
/**
* Show an example to scroll snap
*/
void lv_example_scroll_2(void)
{
lv_obj_t * panel = lv_obj_create(lv_scr_act());
lv_obj_set_size(panel, 280, 120);
lv_obj_set_scroll_snap_x(panel, LV_SCROLL_SNAP_CENTER);
lv_obj_set_flex_flow(panel, LV_FLEX_FLOW_ROW);
lv_obj_align(panel, LV_ALIGN_CENTER, 0, 20);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_obj_t * btn = lv_btn_create(panel);
lv_obj_set_size(btn, 150, lv_pct(100));
lv_obj_t * label = lv_label_create(btn);
if(i == 3) {
lv_label_set_text_fmt(label, "Panel %"LV_PRIu32"\nno snap", i);
lv_obj_clear_flag(btn, LV_OBJ_FLAG_SNAPPABLE);
}
else {
lv_label_set_text_fmt(label, "Panel %"LV_PRIu32, i);
}
lv_obj_center(label);
}
lv_obj_update_snap(panel, LV_ANIM_ON);
#if LV_USE_SWITCH
/*Switch between "One scroll" and "Normal scroll" mode*/
lv_obj_t * sw = lv_switch_create(lv_scr_act());
lv_obj_align(sw, LV_ALIGN_TOP_RIGHT, -20, 10);
lv_obj_add_event_cb(sw, sw_event_cb, LV_EVENT_ALL, panel);
lv_obj_t * label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "One scroll");
lv_obj_align_to(label, sw, LV_ALIGN_OUT_BOTTOM_MID, 0, 5);
#endif
}
#endif
def sw_event_cb(e,panel):
code = e.get_code()
sw = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
if sw.has_state(lv.STATE.CHECKED):
panel.add_flag(lv.obj.FLAG.SCROLL_ONE)
else:
panel.clear_flag(lv.obj.FLAG.SCROLL_ONE)
#
# Show an example to scroll snap
#
panel = lv.obj(lv.scr_act())
panel.set_size(280, 150)
panel.set_scroll_snap_x(lv.SCROLL_SNAP.CENTER)
panel.set_flex_flow(lv.FLEX_FLOW.ROW)
panel.center()
for i in range(10):
btn = lv.btn(panel)
btn.set_size(150, 100)
label = lv.label(btn)
if i == 3:
label.set_text("Panel {:d}\nno snap".format(i))
btn.clear_flag(lv.obj.FLAG.SNAPPABLE)
else:
label.set_text("Panel {:d}".format(i))
label.center()
panel.update_snap(lv.ANIM.ON)
# Switch between "One scroll" and "Normal scroll" mode
sw = lv.switch(lv.scr_act())
sw.align(lv.ALIGN.TOP_RIGHT, -20, 10)
sw.add_event_cb(lambda evt: sw_event_cb(evt,panel), lv.EVENT.ALL, None)
label = lv.label(lv.scr_act())
label.set_text("One scroll")
label.align_to(sw, lv.ALIGN.OUT_BOTTOM_MID, 0, 5)
Floating button¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LIST
static uint32_t btn_cnt = 1;
static void float_btn_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * float_btn = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
lv_obj_t * list = lv_event_get_user_data(e);
char buf[32];
lv_snprintf(buf, sizeof(buf), "Track %d", (int)btn_cnt);
lv_obj_t * list_btn = lv_list_add_btn(list, LV_SYMBOL_AUDIO, buf);
btn_cnt++;
lv_obj_move_foreground(float_btn);
lv_obj_scroll_to_view(list_btn, LV_ANIM_ON);
}
}
/**
* Create a list with a floating button
*/
void lv_example_scroll_3(void)
{
lv_obj_t * list = lv_list_create(lv_scr_act());
lv_obj_set_size(list, 280, 220);
lv_obj_center(list);
for(btn_cnt = 1; btn_cnt <= 2; btn_cnt++) {
char buf[32];
lv_snprintf(buf, sizeof(buf), "Track %d", (int)btn_cnt);
lv_list_add_btn(list, LV_SYMBOL_AUDIO, buf);
}
lv_obj_t * float_btn = lv_btn_create(list);
lv_obj_set_size(float_btn, 50, 50);
lv_obj_add_flag(float_btn, LV_OBJ_FLAG_FLOATING);
lv_obj_align(float_btn, LV_ALIGN_BOTTOM_RIGHT, 0, -lv_obj_get_style_pad_right(list, LV_PART_MAIN));
lv_obj_add_event_cb(float_btn, float_btn_event_cb, LV_EVENT_ALL, list);
lv_obj_set_style_radius(float_btn, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_bg_img_src(float_btn, LV_SYMBOL_PLUS, 0);
lv_obj_set_style_text_font(float_btn, lv_theme_get_font_large(float_btn), 0);
}
#endif
class ScrollExample_3():
def __init__(self):
self.btn_cnt = 1
#
# Create a list with a floating button
#
list = lv.list(lv.scr_act())
list.set_size(280, 220)
list.center()
for btn_cnt in range(2):
list.add_btn(lv.SYMBOL.AUDIO,"Track {:d}".format(btn_cnt))
float_btn = lv.btn(list)
float_btn.set_size(50, 50)
float_btn.add_flag(lv.obj.FLAG.FLOATING)
float_btn.align(lv.ALIGN.BOTTOM_RIGHT, 0, -list.get_style_pad_right(lv.PART.MAIN))
float_btn.add_event_cb(lambda evt: self.float_btn_event_cb(evt,list), lv.EVENT.ALL, None)
float_btn.set_style_radius(lv.RADIUS.CIRCLE, 0)
float_btn.set_style_bg_img_src(lv.SYMBOL.PLUS, 0)
float_btn.set_style_text_font(lv.theme_get_font_large(float_btn), 0)
def float_btn_event_cb(self,e,list):
code = e.get_code()
float_btn = e.get_target()
if code == lv.EVENT.CLICKED:
list_btn = list.add_btn(lv.SYMBOL.AUDIO, "Track {:d}".format(self.btn_cnt))
self.btn_cnt += 1
float_btn.move_foreground()
list_btn.scroll_to_view(lv.ANIM.ON)
scroll_example_3 = ScrollExample_3()
Styling the scrollbars¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LIST
/**
* Styling the scrollbars
*/
void lv_example_scroll_4(void)
{
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_set_size(obj, 200, 100);
lv_obj_center(obj);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label,
"Lorem ipsum dolor sit amet, consectetur adipiscing elit.\n"
"Etiam dictum, tortor vestibulum lacinia laoreet, mi neque consectetur neque, vel mattis odio dolor egestas ligula. \n"
"Sed vestibulum sapien nulla, id convallis ex porttitor nec. \n"
"Duis et massa eu libero accumsan faucibus a in arcu. \n"
"Ut pulvinar odio lorem, vel tempus turpis condimentum quis. Nam consectetur condimentum sem in auctor. \n"
"Sed nisl augue, venenatis in blandit et, gravida ac tortor. \n"
"Etiam dapibus elementum suscipit. \n"
"Proin mollis sollicitudin convallis. \n"
"Integer dapibus tempus arcu nec viverra. \n"
"Donec molestie nulla enim, eu interdum velit placerat quis. \n"
"Donec id efficitur risus, at molestie turpis. \n"
"Suspendisse vestibulum consectetur nunc ut commodo. \n"
"Fusce molestie rhoncus nisi sit amet tincidunt. \n"
"Suspendisse a nunc ut magna ornare volutpat.");
/*Remove the style of scrollbar to have clean start*/
lv_obj_remove_style(obj, NULL, LV_PART_SCROLLBAR | LV_STATE_ANY);
/*Create a transition the animate the some properties on state change*/
static const lv_style_prop_t props[] = {LV_STYLE_BG_OPA, LV_STYLE_WIDTH, 0};
static lv_style_transition_dsc_t trans;
lv_style_transition_dsc_init(&trans, props, lv_anim_path_linear, 200, 0, NULL);
/*Create a style for the scrollbars*/
static lv_style_t style;
lv_style_init(&style);
lv_style_set_width(&style, 4); /*Width of the scrollbar*/
lv_style_set_pad_right(&style, 5); /*Space from the parallel side*/
lv_style_set_pad_top(&style, 5); /*Space from the perpendicular side*/
lv_style_set_radius(&style, 2);
lv_style_set_bg_opa(&style, LV_OPA_70);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_color(&style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_border_width(&style, 2);
lv_style_set_shadow_width(&style, 8);
lv_style_set_shadow_spread(&style, 2);
lv_style_set_shadow_color(&style, lv_palette_darken(LV_PALETTE_BLUE, 1));
lv_style_set_transition(&style, &trans);
/*Make the scrollbars wider and use 100% opacity when scrolled*/
static lv_style_t style_scrolled;
lv_style_init(&style_scrolled);
lv_style_set_width(&style_scrolled, 8);
lv_style_set_bg_opa(&style_scrolled, LV_OPA_COVER);
lv_obj_add_style(obj, &style, LV_PART_SCROLLBAR);
lv_obj_add_style(obj, &style_scrolled, LV_PART_SCROLLBAR | LV_STATE_SCROLLED);
}
#endif
#
# Styling the scrollbars
#
obj = lv.obj(lv.scr_act())
obj.set_size(200, 100)
obj.center()
label = lv.label(obj)
label.set_text(
"""
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Etiam dictum, tortor vestibulum lacinia laoreet, mi neque consectetur neque, vel mattis odio dolor egestas ligula.
Sed vestibulum sapien nulla, id convallis ex porttitor nec.
Duis et massa eu libero accumsan faucibus a in arcu.
Ut pulvinar odio lorem, vel tempus turpis condimentum quis. Nam consectetur condimentum sem in auctor.
Sed nisl augue, venenatis in blandit et, gravida ac tortor.
Etiam dapibus elementum suscipit.
Proin mollis sollicitudin convallis.
Integer dapibus tempus arcu nec viverra.
Donec molestie nulla enim, eu interdum velit placerat quis.
Donec id efficitur risus, at molestie turpis.
Suspendisse vestibulum consectetur nunc ut commodo.
Fusce molestie rhoncus nisi sit amet tincidunt.
Suspendisse a nunc ut magna ornare volutpat.
""")
# Remove the style of scrollbar to have clean start
obj.remove_style(None, lv.PART.SCROLLBAR | lv.STATE.ANY)
# Create a transition the animate the some properties on state change
props = [lv.STYLE.BG_OPA, lv.STYLE.WIDTH, 0]
trans = lv.style_transition_dsc_t()
trans.init(props, lv.anim_t.path_linear, 200, 0, None)
# Create a style for the scrollbars
style = lv.style_t()
style.init()
style.set_width(4) # Width of the scrollbar
style.set_pad_right(5) # Space from the parallel side
style.set_pad_top(5) # Space from the perpendicular side
style.set_radius(2)
style.set_bg_opa(lv.OPA._70)
style.set_bg_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_border_color(lv.palette_darken(lv.PALETTE.BLUE, 3))
style.set_border_width(2)
style.set_shadow_width(8)
style.set_shadow_spread(2)
style.set_shadow_color(lv.palette_darken(lv.PALETTE.BLUE, 1))
style.set_transition(trans)
# Make the scrollbars wider and use 100% opacity when scrolled
style_scrolled = lv.style_t()
style_scrolled.init()
style_scrolled.set_width(8)
style_scrolled.set_bg_opa(lv.OPA.COVER)
obj.add_style(style, lv.PART.SCROLLBAR)
obj.add_style(style_scrolled, lv.PART.SCROLLBAR | lv.STATE.SCROLLED)
Right to left scrolling¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_FONT_DEJAVU_16_PERSIAN_HEBREW
/**
* Scrolling with Right To Left base direction
*/
void lv_example_scroll_5(void)
{
lv_obj_t * obj = lv_obj_create(lv_scr_act());
lv_obj_set_style_base_dir(obj, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(obj, 200, 100);
lv_obj_center(obj);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label,
"میکروکُنترولر (به انگلیسی: Microcontroller) گونهای ریزپردازنده است که دارای حافظهٔ دسترسی تصادفی (RAM) و حافظهٔ فقطخواندنی (ROM)، تایمر، پورتهای ورودی و خروجی (I/O) و درگاه ترتیبی (Serial Port پورت سریال)، درون خود تراشه است، و میتواند به تنهایی ابزارهای دیگر را کنترل کند. به عبارت دیگر یک میکروکنترلر، مدار مجتمع کوچکی است که از یک CPU کوچک و اجزای دیگری مانند تایمر، درگاههای ورودی و خروجی آنالوگ و دیجیتال و حافظه تشکیل شدهاست.");
lv_obj_set_width(label, 400);
lv_obj_set_style_text_font(label, &lv_font_dejavu_16_persian_hebrew, 0);
}
#endif
#
# Scrolling with Right To Left base direction
#
obj = lv.obj(lv.scr_act())
obj.set_style_base_dir(lv.BASE_DIR.RTL, 0)
obj.set_size(200, 100)
obj.center()
label = lv.label(obj)
label.set_text("میکروکُنترولر (به انگلیسی: Microcontroller) گونهای ریزپردازنده است که دارای حافظهٔ دسترسی تصادفی (RAM) و حافظهٔ فقطخواندنی (ROM)، تایمر، پورتهای ورودی و خروجی (I/O) و درگاه ترتیبی (Serial Port پورت سریال)، درون خود تراشه است، و میتواند به تنهایی ابزارهای دیگر را کنترل کند. به عبارت دیگر یک میکروکنترلر، مدار مجتمع کوچکی است که از یک CPU کوچک و اجزای دیگری مانند تایمر، درگاههای ورودی و خروجی آنالوگ و دیجیتال و حافظه تشکیل شدهاست.")
label.set_width(400)
label.set_style_text_font(lv.font_dejavu_16_persian_hebrew, 0)
Translate on scroll¶
C code
GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void scroll_event_cb(lv_event_t * e)
{
lv_obj_t * cont = lv_event_get_target(e);
lv_area_t cont_a;
lv_obj_get_coords(cont, &cont_a);
lv_coord_t cont_y_center = cont_a.y1 + lv_area_get_height(&cont_a) / 2;
lv_coord_t r = lv_obj_get_height(cont) * 7 / 10;
uint32_t i;
uint32_t child_cnt = lv_obj_get_child_cnt(cont);
for(i = 0; i < child_cnt; i++) {
lv_obj_t * child = lv_obj_get_child(cont, i);
lv_area_t child_a;
lv_obj_get_coords(child, &child_a);
lv_coord_t child_y_center = child_a.y1 + lv_area_get_height(&child_a) / 2;
lv_coord_t diff_y = child_y_center - cont_y_center;
diff_y = LV_ABS(diff_y);
/*Get the x of diff_y on a circle.*/
lv_coord_t x;
/*If diff_y is out of the circle use the last point of the circle (the radius)*/
if(diff_y >= r) {
x = r;
}
else {
/*Use Pythagoras theorem to get x from radius and y*/
uint32_t x_sqr = r * r - diff_y * diff_y;
lv_sqrt_res_t res;
lv_sqrt(x_sqr, &res, 0x8000); /*Use lvgl's built in sqrt root function*/
x = r - res.i;
}
/*Translate the item by the calculated X coordinate*/
lv_obj_set_style_translate_x(child, x, 0);
/*Use some opacity with larger translations*/
lv_opa_t opa = lv_map(x, 0, r, LV_OPA_TRANSP, LV_OPA_COVER);
lv_obj_set_style_opa(child, LV_OPA_COVER - opa, 0);
}
}
/**
* Translate the object as they scroll
*/
void lv_example_scroll_6(void)
{
lv_obj_t * cont = lv_obj_create(lv_scr_act());
lv_obj_set_size(cont, 200, 200);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_COLUMN);
lv_obj_add_event_cb(cont, scroll_event_cb, LV_EVENT_SCROLL, NULL);
lv_obj_set_style_radius(cont, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_clip_corner(cont, true, 0);
lv_obj_set_scroll_dir(cont, LV_DIR_VER);
lv_obj_set_scroll_snap_y(cont, LV_SCROLL_SNAP_CENTER);
lv_obj_set_scrollbar_mode(cont, LV_SCROLLBAR_MODE_OFF);
uint32_t i;
for(i = 0; i < 20; i++) {
lv_obj_t * btn = lv_btn_create(cont);
lv_obj_set_width(btn, lv_pct(100));
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text_fmt(label, "Button %"LV_PRIu32, i);
}
/*Update the buttons position manually for first*/
lv_event_send(cont, LV_EVENT_SCROLL, NULL);
/*Be sure the fist button is in the middle*/
lv_obj_scroll_to_view(lv_obj_get_child(cont, 0), LV_ANIM_OFF);
}
#endif
def scroll_event_cb(e):
cont = e.get_target()
cont_a = lv.area_t()
cont.get_coords(cont_a)
cont_y_center = cont_a.y1 + cont_a.get_height() // 2
r = cont.get_height() * 7 // 10
child_cnt = cont.get_child_cnt()
for i in range(child_cnt):
child = cont.get_child(i)
child_a = lv.area_t()
child.get_coords(child_a)
child_y_center = child_a.y1 + child_a.get_height() // 2
diff_y = child_y_center - cont_y_center
diff_y = abs(diff_y)
# Get the x of diff_y on a circle.
# If diff_y is out of the circle use the last point of the circle (the radius)
if diff_y >= r:
x = r
else:
# Use Pythagoras theorem to get x from radius and y
x_sqr = r * r - diff_y * diff_y
res = lv.sqrt_res_t()
lv.sqrt(x_sqr, res, 0x8000) # Use lvgl's built in sqrt root function
x = r - res.i
# Translate the item by the calculated X coordinate
child.set_style_translate_x(x, 0)
# Use some opacity with larger translations
opa = lv.map(x, 0, r, lv.OPA.TRANSP, lv.OPA.COVER)
child.set_style_opa(lv.OPA.COVER - opa, 0)
#
# Translate the object as they scroll
#
cont = lv.obj(lv.scr_act())
cont.set_size(200, 200)
cont.center()
cont.set_flex_flow(lv.FLEX_FLOW.COLUMN)
cont.add_event_cb(scroll_event_cb, lv.EVENT.SCROLL, None)
cont.set_style_radius(lv.RADIUS.CIRCLE, 0)
cont.set_style_clip_corner(True, 0)
cont.set_scroll_dir(lv.DIR.VER)
cont.set_scroll_snap_y(lv.SCROLL_SNAP.CENTER)
cont.set_scrollbar_mode(lv.SCROLLBAR_MODE.OFF)
for i in range(20):
btn = lv.btn(cont)
btn.set_width(lv.pct(100))
label = lv.label(btn)
label.set_text("Button " + str(i))
# Update the buttons position manually for first*
lv.event_send(cont, lv.EVENT.SCROLL, None)
# Be sure the fist button is in the middle
#lv.obj.scroll_to_view(cont.get_child(0), lv.ANIM.OFF)
cont.get_child(0).scroll_to_view(lv.ANIM.OFF)
Widgets¶
Base object¶
Base objects with custom styles¶
C code
GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES
void lv_example_obj_1(void)
{
lv_obj_t * obj1;
obj1 = lv_obj_create(lv_scr_act());
lv_obj_set_size(obj1, 100, 50);
lv_obj_align(obj1, LV_ALIGN_CENTER, -60, -30);
static lv_style_t style_shadow;
lv_style_init(&style_shadow);
lv_style_set_shadow_width(&style_shadow, 10);
lv_style_set_shadow_spread(&style_shadow, 5);
lv_style_set_shadow_color(&style_shadow, lv_palette_main(LV_PALETTE_BLUE));
lv_obj_t * obj2;
obj2 = lv_obj_create(lv_scr_act());
lv_obj_add_style(obj2, &style_shadow, 0);
lv_obj_align(obj2, LV_ALIGN_CENTER, 60, 30);
}
#endif
obj1 = lv.obj(lv.scr_act())
obj1.set_size(100, 50)
obj1.align(lv.ALIGN.CENTER, -60, -30)
style_shadow = lv.style_t()
style_shadow.init()
style_shadow.set_shadow_width(10)
style_shadow.set_shadow_spread(5)
style_shadow.set_shadow_color(lv.palette_main(lv.PALETTE.BLUE))
obj2 = lv.obj(lv.scr_act())
obj2.add_style(style_shadow, 0)
obj2.align(lv.ALIGN.CENTER, 60, 30)
Make an object draggable¶
C code
GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES
static void drag_event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_indev_t * indev = lv_indev_get_act();
if(indev == NULL) return;
lv_point_t vect;
lv_indev_get_vect(indev, &vect);
lv_coord_t x = lv_obj_get_x(obj) + vect.x;
lv_coord_t y = lv_obj_get_y(obj) + vect.y;
lv_obj_set_pos(obj, x, y);
}
/**
* Make an object dragable.
*/
void lv_example_obj_2(void)
{
lv_obj_t * obj;
obj = lv_obj_create(lv_scr_act());
lv_obj_set_size(obj, 150, 100);
lv_obj_add_event_cb(obj, drag_event_handler, LV_EVENT_PRESSING, NULL);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label, "Drag me");
lv_obj_center(label);
}
#endif
def drag_event_handler(e):
obj = e.get_target()
indev = lv.indev_get_act()
vect = lv.point_t()
indev.get_vect(vect)
x = obj.get_x() + vect.x
y = obj.get_y() + vect.y
obj.set_pos(x, y)
#
# Make an object dragable.
#
obj = lv.obj(lv.scr_act())
obj.set_size(150, 100)
obj.add_event_cb(drag_event_handler, lv.EVENT.PRESSING, None)
label = lv.label(obj)
label.set_text("Drag me")
label.center()
Arc¶
Simple Arc¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_ARC && LV_BUILD_EXAMPLES
static void value_changed_event_cb(lv_event_t * e);
void lv_example_arc_1(void)
{
lv_obj_t * label = lv_label_create(lv_scr_act());
/*Create an Arc*/
lv_obj_t * arc = lv_arc_create(lv_scr_act());
lv_obj_set_size(arc, 150, 150);
lv_arc_set_rotation(arc, 135);
lv_arc_set_bg_angles(arc, 0, 270);
lv_arc_set_value(arc, 10);
lv_obj_center(arc);
lv_obj_add_event_cb(arc, value_changed_event_cb, LV_EVENT_VALUE_CHANGED, label);
/*Manually update the label for the first time*/
lv_event_send(arc, LV_EVENT_VALUE_CHANGED, NULL);
}
static void value_changed_event_cb(lv_event_t * e)
{
lv_obj_t * arc = lv_event_get_target(e);
lv_obj_t * label = lv_event_get_user_data(e);
lv_label_set_text_fmt(label, "%d%%", lv_arc_get_value(arc));
/*Rotate the label to the current position of the arc*/
lv_arc_rotate_obj_to_angle(arc, label, 25);
}
#endif
# Create an Arc
arc = lv.arc(lv.scr_act())
arc.set_end_angle(200)
arc.set_size(150, 150)
arc.center()
Loader with Arc¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_ARC && LV_BUILD_EXAMPLES
static void set_angle(void * obj, int32_t v)
{
lv_arc_set_value(obj, v);
}
/**
* Create an arc which acts as a loader.
*/
void lv_example_arc_2(void)
{
/*Create an Arc*/
lv_obj_t * arc = lv_arc_create(lv_scr_act());
lv_arc_set_rotation(arc, 270);
lv_arc_set_bg_angles(arc, 0, 360);
lv_obj_remove_style(arc, NULL, LV_PART_KNOB); /*Be sure the knob is not displayed*/
lv_obj_clear_flag(arc, LV_OBJ_FLAG_CLICKABLE); /*To not allow adjusting by click*/
lv_obj_center(arc);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, arc);
lv_anim_set_exec_cb(&a, set_angle);
lv_anim_set_time(&a, 1000);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE); /*Just for the demo*/
lv_anim_set_repeat_delay(&a, 500);
lv_anim_set_values(&a, 0, 100);
lv_anim_start(&a);
}
#endif
#
# An `lv_timer` to call periodically to set the angles of the arc
#
class ArcLoader():
def __init__(self):
self.a = 270
def arc_loader_cb(self,tim,arc):
# print(tim,arc)
self.a += 5
arc.set_end_angle(self.a)
if self.a >= 270 + 360:
tim._del()
#
# Create an arc which acts as a loader.
#
# Create an Arc
arc = lv.arc(lv.scr_act())
arc.set_bg_angles(0, 360)
arc.set_angles(270, 270)
arc.center()
# create the loader
arc_loader = ArcLoader()
# Create an `lv_timer` to update the arc.
timer = lv.timer_create_basic()
timer.set_period(20)
timer.set_cb(lambda src: arc_loader.arc_loader_cb(timer,arc))
Bar¶
Simple Bar¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
void lv_example_bar_1(void)
{
lv_obj_t * bar1 = lv_bar_create(lv_scr_act());
lv_obj_set_size(bar1, 200, 20);
lv_obj_center(bar1);
lv_bar_set_value(bar1, 70, LV_ANIM_OFF);
}
#endif
bar1 = lv.bar(lv.scr_act())
bar1.set_size(200, 20)
bar1.center()
bar1.set_value(70, lv.ANIM.OFF)
Styling a bar¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Example of styling the bar
*/
void lv_example_bar_2(void)
{
static lv_style_t style_bg;
static lv_style_t style_indic;
lv_style_init(&style_bg);
lv_style_set_border_color(&style_bg, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_width(&style_bg, 2);
lv_style_set_pad_all(&style_bg, 6); /*To make the indicator smaller*/
lv_style_set_radius(&style_bg, 6);
lv_style_set_anim_time(&style_bg, 1000);
lv_style_init(&style_indic);
lv_style_set_bg_opa(&style_indic, LV_OPA_COVER);
lv_style_set_bg_color(&style_indic, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_radius(&style_indic, 3);
lv_obj_t * bar = lv_bar_create(lv_scr_act());
lv_obj_remove_style_all(bar); /*To have a clean start*/
lv_obj_add_style(bar, &style_bg, 0);
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 200, 20);
lv_obj_center(bar);
lv_bar_set_value(bar, 100, LV_ANIM_ON);
}
#endif
#
# Example of styling the bar
#
style_bg = lv.style_t()
style_indic = lv.style_t()
style_bg.init()
style_bg.set_border_color(lv.palette_main(lv.PALETTE.BLUE))
style_bg.set_border_width(2)
style_bg.set_pad_all(6) # To make the indicator smaller
style_bg.set_radius(6)
style_bg.set_anim_time(1000)
style_indic.init()
style_indic.set_bg_opa(lv.OPA.COVER)
style_indic.set_bg_color(lv.palette_main(lv.PALETTE.BLUE))
style_indic.set_radius(3)
bar = lv.bar(lv.scr_act())
bar.remove_style_all() # To have a clean start
bar.add_style(style_bg, 0)
bar.add_style(style_indic, lv.PART.INDICATOR)
bar.set_size(200, 20)
bar.center()
bar.set_value(100, lv.ANIM.ON)
Temperature meter¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
static void set_temp(void * bar, int32_t temp)
{
lv_bar_set_value(bar, temp, LV_ANIM_ON);
}
/**
* A temperature meter example
*/
void lv_example_bar_3(void)
{
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_opa(&style_indic, LV_OPA_COVER);
lv_style_set_bg_color(&style_indic, lv_palette_main(LV_PALETTE_RED));
lv_style_set_bg_grad_color(&style_indic, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_bg_grad_dir(&style_indic, LV_GRAD_DIR_VER);
lv_obj_t * bar = lv_bar_create(lv_scr_act());
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 20, 200);
lv_obj_center(bar);
lv_bar_set_range(bar, -20, 40);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_exec_cb(&a, set_temp);
lv_anim_set_time(&a, 3000);
lv_anim_set_playback_time(&a, 3000);
lv_anim_set_var(&a, bar);
lv_anim_set_values(&a, -20, 40);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
def set_temp(bar, temp):
bar.set_value(temp, lv.ANIM.ON)
#
# A temperature meter example
#
style_indic = lv.style_t()
style_indic.init()
style_indic.set_bg_opa(lv.OPA.COVER)
style_indic.set_bg_color(lv.palette_main(lv.PALETTE.RED))
style_indic.set_bg_grad_color(lv.palette_main(lv.PALETTE.BLUE))
style_indic.set_bg_grad_dir(lv.GRAD_DIR.VER)
bar = lv.bar(lv.scr_act())
bar.add_style(style_indic, lv.PART.INDICATOR)
bar.set_size(20, 200)
bar.center()
bar.set_range(-20, 40)
a = lv.anim_t()
a.init()
a.set_time(3000)
a.set_playback_time(3000)
a.set_var(bar)
a.set_values(-20, 40)
a.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a.set_custom_exec_cb(lambda a, val: set_temp(bar,val))
lv.anim_t.start(a)
Stripe pattern and range value¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Bar with stripe pattern and ranged value
*/
void lv_example_bar_4(void)
{
LV_IMG_DECLARE(img_skew_strip);
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_img_src(&style_indic, &img_skew_strip);
lv_style_set_bg_img_tiled(&style_indic, true);
lv_style_set_bg_img_opa(&style_indic, LV_OPA_30);
lv_obj_t * bar = lv_bar_create(lv_scr_act());
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 260, 20);
lv_obj_center(bar);
lv_bar_set_mode(bar, LV_BAR_MODE_RANGE);
lv_bar_set_value(bar, 90, LV_ANIM_OFF);
lv_bar_set_start_value(bar, 20, LV_ANIM_OFF);
}
#endif
#
# get an icon
#
def get_icon(filename,xres,yres):
try:
sdl_filename = "../../assets/" + filename + "_" + str(xres) + "x" + str(yres) + "_argb8888.fnt"
print("file name: ", sdl_filename)
with open(sdl_filename,'rb') as f:
icon_data = f.read()
except:
print("Could not find image file: " + filename)
return None
icon_dsc = lv.img_dsc_t(
{
"header": {"always_zero": 0, "w": xres, "h": yres, "cf": lv.img.CF.TRUE_COLOR_ALPHA},
"data": icon_data,
"data_size": len(icon_data),
}
)
return icon_dsc
#
# Bar with stripe pattern and ranged value
#
img_skew_strip_dsc = get_icon("img_skew_strip",80,20)
style_indic = lv.style_t()
style_indic.init()
style_indic.set_bg_img_src(img_skew_strip_dsc)
style_indic.set_bg_img_tiled(True)
style_indic.set_bg_img_opa(lv.OPA._30)
bar = lv.bar(lv.scr_act())
bar.add_style(style_indic, lv.PART.INDICATOR)
bar.set_size(260, 20)
bar.center()
bar.set_mode(lv.bar.MODE.RANGE)
bar.set_value(90, lv.ANIM.OFF)
bar.set_start_value(20, lv.ANIM.OFF)
Bar with LTR and RTL base direction¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Bar with LTR and RTL base direction
*/
void lv_example_bar_5(void)
{
lv_obj_t * label;
lv_obj_t * bar_ltr = lv_bar_create(lv_scr_act());
lv_obj_set_size(bar_ltr, 200, 20);
lv_bar_set_value(bar_ltr, 70, LV_ANIM_OFF);
lv_obj_align(bar_ltr, LV_ALIGN_CENTER, 0, -30);
label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "Left to Right base direction");
lv_obj_align_to(label, bar_ltr, LV_ALIGN_OUT_TOP_MID, 0, -5);
lv_obj_t * bar_rtl = lv_bar_create(lv_scr_act());
lv_obj_set_style_base_dir(bar_rtl, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(bar_rtl, 200, 20);
lv_bar_set_value(bar_rtl, 70, LV_ANIM_OFF);
lv_obj_align(bar_rtl, LV_ALIGN_CENTER, 0, 30);
label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "Right to Left base direction");
lv_obj_align_to(label, bar_rtl, LV_ALIGN_OUT_TOP_MID, 0, -5);
}
#endif
#
# Bar with LTR and RTL base direction
#
bar_ltr = lv.bar(lv.scr_act())
bar_ltr.set_size(200, 20)
bar_ltr.set_value(70, lv.ANIM.OFF)
bar_ltr.align(lv.ALIGN.CENTER, 0, -30)
label = lv.label(lv.scr_act())
label.set_text("Left to Right base direction")
label.align_to(bar_ltr, lv.ALIGN.OUT_TOP_MID, 0, -5)
bar_rtl = lv.bar(lv.scr_act())
bar_rtl.set_style_base_dir(lv.BASE_DIR.RTL,0)
bar_rtl.set_size(200, 20)
bar_rtl.set_value(70, lv.ANIM.OFF)
bar_rtl.align(lv.ALIGN.CENTER, 0, 30)
label = lv.label(lv.scr_act())
label.set_text("Right to Left base direction")
label.align_to(bar_rtl, lv.ALIGN.OUT_TOP_MID, 0, -5)
Custom drawer to show the current value¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
static void set_value(void * bar, int32_t v)
{
lv_bar_set_value(bar, v, LV_ANIM_OFF);
}
static void event_cb(lv_event_t * e)
{
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(dsc->part != LV_PART_INDICATOR) return;
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.font = LV_FONT_DEFAULT;
char buf[8];
lv_snprintf(buf, sizeof(buf), "%d", (int)lv_bar_get_value(obj));
lv_point_t txt_size;
lv_txt_get_size(&txt_size, buf, label_dsc.font, label_dsc.letter_space, label_dsc.line_space, LV_COORD_MAX,
label_dsc.flag);
lv_area_t txt_area;
/*If the indicator is long enough put the text inside on the right*/
if(lv_area_get_width(dsc->draw_area) > txt_size.x + 20) {
txt_area.x2 = dsc->draw_area->x2 - 5;
txt_area.x1 = txt_area.x2 - txt_size.x + 1;
label_dsc.color = lv_color_white();
}
/*If the indicator is still short put the text out of it on the right*/
else {
txt_area.x1 = dsc->draw_area->x2 + 5;
txt_area.x2 = txt_area.x1 + txt_size.x - 1;
label_dsc.color = lv_color_black();
}
txt_area.y1 = dsc->draw_area->y1 + (lv_area_get_height(dsc->draw_area) - txt_size.y) / 2;
txt_area.y2 = txt_area.y1 + txt_size.y - 1;
lv_draw_label(dsc->draw_ctx, &label_dsc, &txt_area, buf, NULL);
}
/**
* Custom drawer on the bar to display the current value
*/
void lv_example_bar_6(void)
{
lv_obj_t * bar = lv_bar_create(lv_scr_act());
lv_obj_add_event_cb(bar, event_cb, LV_EVENT_DRAW_PART_END, NULL);
lv_obj_set_size(bar, 200, 20);
lv_obj_center(bar);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, bar);
lv_anim_set_values(&a, 0, 100);
lv_anim_set_exec_cb(&a, set_value);
lv_anim_set_time(&a, 2000);
lv_anim_set_playback_time(&a, 2000);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
def set_value(bar, v):
bar.set_value(v, lv.ANIM.OFF)
def event_cb(e):
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
if dsc.part != lv.PART.INDICATOR:
return
obj= e.get_target()
label_dsc = lv.draw_label_dsc_t()
label_dsc.init()
# label_dsc.font = LV_FONT_DEFAULT;
value_txt = str(obj.get_value())
txt_size = lv.point_t()
lv.txt_get_size(txt_size, value_txt, label_dsc.font, label_dsc.letter_space, label_dsc.line_space, lv.COORD.MAX, label_dsc.flag)
txt_area = lv.area_t()
# If the indicator is long enough put the text inside on the right
if dsc.draw_area.get_width() > txt_size.x + 20:
txt_area.x2 = dsc.draw_area.x2 - 5
txt_area.x1 = txt_area.x2 - txt_size.x + 1
label_dsc.color = lv.color_white()
# If the indicator is still short put the text out of it on the right*/
else:
txt_area.x1 = dsc.draw_area.x2 + 5
txt_area.x2 = txt_area.x1 + txt_size.x - 1
label_dsc.color = lv.color_black()
txt_area.y1 = dsc.draw_area.y1 + (dsc.draw_area.get_height() - txt_size.y) // 2
txt_area.y2 = txt_area.y1 + txt_size.y - 1
dsc.draw_ctx.label(label_dsc, txt_area, value_txt, None)
#
# Custom drawer on the bar to display the current value
#
bar = lv.bar(lv.scr_act())
bar.add_event_cb(event_cb, lv.EVENT.DRAW_PART_END, None)
bar.set_size(200, 20)
bar.center()
a = lv.anim_t()
a.init()
a.set_var(bar)
a.set_values(0, 100)
a.set_custom_exec_cb(lambda a,val: set_value(bar,val))
a.set_time(2000)
a.set_playback_time(2000)
a.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
lv.anim_t.start(a)
Button¶
Simple Buttons¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BTN && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_CLICKED) {
LV_LOG_USER("Clicked");
}
else if(code == LV_EVENT_VALUE_CHANGED) {
LV_LOG_USER("Toggled");
}
}
void lv_example_btn_1(void)
{
lv_obj_t * label;
lv_obj_t * btn1 = lv_btn_create(lv_scr_act());
lv_obj_add_event_cb(btn1, event_handler, LV_EVENT_ALL, NULL);
lv_obj_align(btn1, LV_ALIGN_CENTER, 0, -40);
label = lv_label_create(btn1);
lv_label_set_text(label, "Button");
lv_obj_center(label);
lv_obj_t * btn2 = lv_btn_create(lv_scr_act());
lv_obj_add_event_cb(btn2, event_handler, LV_EVENT_ALL, NULL);
lv_obj_align(btn2, LV_ALIGN_CENTER, 0, 40);
lv_obj_add_flag(btn2, LV_OBJ_FLAG_CHECKABLE);
lv_obj_set_height(btn2, LV_SIZE_CONTENT);
label = lv_label_create(btn2);
lv_label_set_text(label, "Toggle");
lv_obj_center(label);
}
#endif
def event_handler(evt):
code = evt.get_code()
if code == lv.EVENT.CLICKED:
print("Clicked event seen")
elif code == lv.EVENT.VALUE_CHANGED:
print("Value changed seen")
# create a simple button
btn1 = lv.btn(lv.scr_act())
# attach the callback
btn1.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn1.align(lv.ALIGN.CENTER,0,-40)
label=lv.label(btn1)
label.set_text("Button")
# create a toggle button
btn2 = lv.btn(lv.scr_act())
# attach the callback
#btn2.add_event_cb(event_handler,lv.EVENT.VALUE_CHANGED,None)
btn2.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn2.align(lv.ALIGN.CENTER,0,40)
btn2.add_flag(lv.obj.FLAG.CHECKABLE)
btn2.set_height(lv.SIZE.CONTENT)
label=lv.label(btn2)
label.set_text("Toggle")
label.center()
Styling buttons¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BTN && LV_BUILD_EXAMPLES
/**
* Style a button from scratch
*/
void lv_example_btn_2(void)
{
/*Init the style for the default state*/
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 3);
lv_style_set_bg_opa(&style, LV_OPA_100);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_bg_grad_color(&style, lv_palette_darken(LV_PALETTE_BLUE, 2));
lv_style_set_bg_grad_dir(&style, LV_GRAD_DIR_VER);
lv_style_set_border_opa(&style, LV_OPA_40);
lv_style_set_border_width(&style, 2);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_shadow_width(&style, 8);
lv_style_set_shadow_color(&style, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_shadow_ofs_y(&style, 8);
lv_style_set_outline_opa(&style, LV_OPA_COVER);
lv_style_set_outline_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_text_color(&style, lv_color_white());
lv_style_set_pad_all(&style, 10);
/*Init the pressed style*/
static lv_style_t style_pr;
lv_style_init(&style_pr);
/*Add a large outline when pressed*/
lv_style_set_outline_width(&style_pr, 30);
lv_style_set_outline_opa(&style_pr, LV_OPA_TRANSP);
lv_style_set_translate_y(&style_pr, 5);
lv_style_set_shadow_ofs_y(&style_pr, 3);
lv_style_set_bg_color(&style_pr, lv_palette_darken(LV_PALETTE_BLUE, 2));
lv_style_set_bg_grad_color(&style_pr, lv_palette_darken(LV_PALETTE_BLUE, 4));
/*Add a transition to the outline*/
static lv_style_transition_dsc_t trans;
static lv_style_prop_t props[] = {LV_STYLE_OUTLINE_WIDTH, LV_STYLE_OUTLINE_OPA, 0};
lv_style_transition_dsc_init(&trans, props, lv_anim_path_linear, 300, 0, NULL);
lv_style_set_transition(&style_pr, &trans);
lv_obj_t * btn1 = lv_btn_create(lv_scr_act());
lv_obj_remove_style_all(btn1); /*Remove the style coming from the theme*/
lv_obj_add_style(btn1, &style, 0);
lv_obj_add_style(btn1, &style_pr, LV_STATE_PRESSED);
lv_obj_set_size(btn1, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_center(btn1);
lv_obj_t * label = lv_label_create(btn1);
lv_label_set_text(label, "Button");
lv_obj_center(label);
}
#endif
#
# Style a button from scratch
#
# Init the style for the default state
style = lv.style_t()
style.init()
style.set_radius(3)
style.set_bg_opa(lv.OPA.COVER)
style.set_bg_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_bg_grad_color(lv.palette_darken(lv.PALETTE.BLUE, 2))
style.set_bg_grad_dir(lv.GRAD_DIR.VER)
style.set_border_opa(lv.OPA._40)
style.set_border_width(2)
style.set_border_color(lv.palette_main(lv.PALETTE.GREY))
style.set_shadow_width(8)
style.set_shadow_color(lv.palette_main(lv.PALETTE.GREY))
style.set_shadow_ofs_y(8)
style.set_outline_opa(lv.OPA.COVER)
style.set_outline_color(lv.palette_main(lv.PALETTE.BLUE))
style.set_text_color(lv.color_white())
style.set_pad_all(10)
# Init the pressed style
style_pr = lv.style_t()
style_pr.init()
# Add a large outline when pressed
style_pr.set_outline_width(30)
style_pr.set_outline_opa(lv.OPA.TRANSP)
style_pr.set_translate_y(5)
style_pr.set_shadow_ofs_y(3)
style_pr.set_bg_color(lv.palette_darken(lv.PALETTE.BLUE, 2))
style_pr.set_bg_grad_color(lv.palette_darken(lv.PALETTE.BLUE, 4))
# Add a transition to the outline
trans = lv.style_transition_dsc_t()
props = [lv.STYLE.OUTLINE_WIDTH, lv.STYLE.OUTLINE_OPA, 0]
trans.init(props, lv.anim_t.path_linear, 300, 0, None)
style_pr.set_transition(trans)
btn1 = lv.btn(lv.scr_act())
btn1.remove_style_all() # Remove the style coming from the theme
btn1.add_style(style, 0)
btn1.add_style(style_pr, lv.STATE.PRESSED)
btn1.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
btn1.center()
label = lv.label(btn1)
label.set_text("Button")
label.center()
Gummy button¶
C code
GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_BTN
/**
* Create a style transition on a button to act like a gum when clicked
*/
void lv_example_btn_3(void)
{
/*Properties to transition*/
static lv_style_prop_t props[] = {
LV_STYLE_TRANSFORM_WIDTH, LV_STYLE_TRANSFORM_HEIGHT, LV_STYLE_TEXT_LETTER_SPACE, 0
};
/*Transition descriptor when going back to the default state.
*Add some delay to be sure the press transition is visible even if the press was very short*/
static lv_style_transition_dsc_t transition_dsc_def;
lv_style_transition_dsc_init(&transition_dsc_def, props, lv_anim_path_overshoot, 250, 100, NULL);
/*Transition descriptor when going to pressed state.
*No delay, go to presses state immediately*/
static lv_style_transition_dsc_t transition_dsc_pr;
lv_style_transition_dsc_init(&transition_dsc_pr, props, lv_anim_path_ease_in_out, 250, 0, NULL);
/*Add only the new transition to he default state*/
static lv_style_t style_def;
lv_style_init(&style_def);
lv_style_set_transition(&style_def, &transition_dsc_def);
/*Add the transition and some transformation to the presses state.*/
static lv_style_t style_pr;
lv_style_init(&style_pr);
lv_style_set_transform_width(&style_pr, 10);
lv_style_set_transform_height(&style_pr, -10);
lv_style_set_text_letter_space(&style_pr, 10);
lv_style_set_transition(&style_pr, &transition_dsc_pr);
lv_obj_t * btn1 = lv_btn_create(lv_scr_act());
lv_obj_align(btn1, LV_ALIGN_CENTER, 0, -80);
lv_obj_add_style(btn1, &style_pr, LV_STATE_PRESSED);
lv_obj_add_style(btn1, &style_def, 0);
lv_obj_t * label = lv_label_create(btn1);
lv_label_set_text(label, "Gum");
}
#endif
#
# Create a style transition on a button to act like a gum when clicked
#
# Properties to transition
props = [lv.STYLE.TRANSFORM_WIDTH, lv.STYLE.TRANSFORM_HEIGHT, lv.STYLE.TEXT_LETTER_SPACE, 0]
# Transition descriptor when going back to the default state.
# Add some delay to be sure the press transition is visible even if the press was very short*/
transition_dsc_def = lv.style_transition_dsc_t()
transition_dsc_def.init(props, lv.anim_t.path_overshoot, 250, 100, None)
# Transition descriptor when going to pressed state.
# No delay, go to pressed state immediately
transition_dsc_pr = lv.style_transition_dsc_t()
transition_dsc_pr.init(props, lv.anim_t.path_ease_in_out, 250, 0, None)
# Add only the new transition to the default state
style_def = lv.style_t()
style_def.init()
style_def.set_transition(transition_dsc_def)
# Add the transition and some transformation to the presses state.
style_pr = lv.style_t()
style_pr.init()
style_pr.set_transform_width(10)
style_pr.set_transform_height(-10)
style_pr.set_text_letter_space(10)
style_pr.set_transition(transition_dsc_pr)
btn1 = lv.btn(lv.scr_act())
btn1.align(lv.ALIGN.CENTER, 0, -80)
btn1.add_style(style_pr, lv.STATE.PRESSED)
btn1.add_style(style_def, 0)
label = lv.label(btn1)
label.set_text("Gum")
Button matrix¶
Simple Button matrix¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BTNMATRIX && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
uint32_t id = lv_btnmatrix_get_selected_btn(obj);
const char * txt = lv_btnmatrix_get_btn_text(obj, id);
LV_LOG_USER("%s was pressed\n", txt);
}
}
static const char * btnm_map[] = {"1", "2", "3", "4", "5", "\n",
"6", "7", "8", "9", "0", "\n",
"Action1", "Action2", ""
};
void lv_example_btnmatrix_1(void)
{
lv_obj_t * btnm1 = lv_btnmatrix_create(lv_scr_act());
lv_btnmatrix_set_map(btnm1, btnm_map);
lv_btnmatrix_set_btn_width(btnm1, 10, 2); /*Make "Action1" twice as wide as "Action2"*/
lv_btnmatrix_set_btn_ctrl(btnm1, 10, LV_BTNMATRIX_CTRL_CHECKABLE);
lv_btnmatrix_set_btn_ctrl(btnm1, 11, LV_BTNMATRIX_CTRL_CHECKED);
lv_obj_align(btnm1, LV_ALIGN_CENTER, 0, 0);
lv_obj_add_event_cb(btnm1, event_handler, LV_EVENT_ALL, NULL);
}
#endif
def event_handler(evt):
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.VALUE_CHANGED :
id = obj.get_selected_btn()
txt = obj.get_btn_text(id)
print("%s was pressed"%txt)
btnm_map = ["1", "2", "3", "4", "5", "\n",
"6", "7", "8", "9", "0", "\n",
"Action1", "Action2", ""]
btnm1 = lv.btnmatrix(lv.scr_act())
btnm1.set_map(btnm_map)
btnm1.set_btn_width(10, 2) # Make "Action1" twice as wide as "Action2"
btnm1.set_btn_ctrl(10, lv.btnmatrix.CTRL.CHECKABLE)
btnm1.set_btn_ctrl(11, lv.btnmatrix.CTRL.CHECKED)
btnm1.align(lv.ALIGN.CENTER, 0, 0)
btnm1.add_event_cb(event_handler, lv.EVENT.ALL, None)
#endif
Custom buttons¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BTNMATRIX && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_DRAW_PART_BEGIN) {
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
/*When the button matrix draws the buttons...*/
if(dsc->class_p == &lv_btnmatrix_class && dsc->type == LV_BTNMATRIX_DRAW_PART_BTN) {
/*Change the draw descriptor of the 2nd button*/
if(dsc->id == 1) {
dsc->rect_dsc->radius = 0;
if(lv_btnmatrix_get_selected_btn(obj) == dsc->id) dsc->rect_dsc->bg_color = lv_palette_darken(LV_PALETTE_BLUE, 3);
else dsc->rect_dsc->bg_color = lv_palette_main(LV_PALETTE_BLUE);
dsc->rect_dsc->shadow_width = 6;
dsc->rect_dsc->shadow_ofs_x = 3;
dsc->rect_dsc->shadow_ofs_y = 3;
dsc->label_dsc->color = lv_color_white();
}
/*Change the draw descriptor of the 3rd button*/
else if(dsc->id == 2) {
dsc->rect_dsc->radius = LV_RADIUS_CIRCLE;
if(lv_btnmatrix_get_selected_btn(obj) == dsc->id) dsc->rect_dsc->bg_color = lv_palette_darken(LV_PALETTE_RED, 3);
else dsc->rect_dsc->bg_color = lv_palette_main(LV_PALETTE_RED);
dsc->label_dsc->color = lv_color_white();
}
else if(dsc->id == 3) {
dsc->label_dsc->opa = LV_OPA_TRANSP; /*Hide the text if any*/
}
}
}
if(code == LV_EVENT_DRAW_PART_END) {
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
/*When the button matrix draws the buttons...*/
if(dsc->class_p == &lv_btnmatrix_class && dsc->type == LV_BTNMATRIX_DRAW_PART_BTN) {
/*Add custom content to the 4th button when the button itself was drawn*/
if(dsc->id == 3) {
LV_IMG_DECLARE(img_star);
lv_img_header_t header;
lv_res_t res = lv_img_decoder_get_info(&img_star, &header);
if(res != LV_RES_OK) return;
lv_area_t a;
a.x1 = dsc->draw_area->x1 + (lv_area_get_width(dsc->draw_area) - header.w) / 2;
a.x2 = a.x1 + header.w - 1;
a.y1 = dsc->draw_area->y1 + (lv_area_get_height(dsc->draw_area) - header.h) / 2;
a.y2 = a.y1 + header.h - 1;
lv_draw_img_dsc_t img_draw_dsc;
lv_draw_img_dsc_init(&img_draw_dsc);
img_draw_dsc.recolor = lv_color_black();
if(lv_btnmatrix_get_selected_btn(obj) == dsc->id) img_draw_dsc.recolor_opa = LV_OPA_30;
lv_draw_img(dsc->draw_ctx, &img_draw_dsc, &a, &img_star);
}
}
}
}
/**
* Add custom drawer to the button matrix to customize buttons one by one
*/
void lv_example_btnmatrix_2(void)
{
lv_obj_t * btnm = lv_btnmatrix_create(lv_scr_act());
lv_obj_add_event_cb(btnm, event_cb, LV_EVENT_ALL, NULL);
lv_obj_center(btnm);
}
#endif
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_star.png','rb') as f:
png_data = f.read()
except:
print("Could not find star.png")
sys.exit()
img_star_argb = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
def event_cb(e):
code = e.get_code()
obj = e.get_target()
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
if code == lv.EVENT.DRAW_PART_BEGIN:
# Change the draw descriptor the 2nd button
if dsc.id == 1:
dsc.rect_dsc.radius = 0
if obj.get_selected_btn() == dsc.id:
dsc.rect_dsc.bg_color = lv.palette_darken(lv.PALETTE.GREY, 3)
else:
dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.BLUE)
dsc.rect_dsc.shadow_width = 6
dsc.rect_dsc.shadow_ofs_x = 3
dsc.rect_dsc.shadow_ofs_y = 3
dsc.label_dsc.color = lv.color_white()
# Change the draw descriptor the 3rd button
elif dsc.id == 2:
dsc.rect_dsc.radius = lv.RADIUS.CIRCLE
if obj.get_selected_btn() == dsc.id:
dsc.rect_dsc.bg_color = lv.palette_darken(lv.PALETTE.RED, 3)
else:
dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.RED)
dsc.label_dsc.color = lv.color_white()
elif dsc.id == 3:
dsc.label_dsc.opa = lv.OPA.TRANSP # Hide the text if any
if code == lv.EVENT.DRAW_PART_END:
# Add custom content to the 4th button when the button itself was drawn
if dsc.id == 3:
# LV_IMG_DECLARE(img_star)
header = lv.img_header_t()
res = lv.img.decoder_get_info(img_star_argb, header)
if res != lv.RES.OK:
print("error when getting image header")
return
else:
a = lv.area_t()
a.x1 = dsc.draw_area.x1 + (dsc.draw_area.get_width() - header.w) // 2
a.x2 = a.x1 + header.w - 1
a.y1 = dsc.draw_area.y1 + (dsc.draw_area.get_height() - header.h) // 2
a.y2 = a.y1 + header.h - 1
img_draw_dsc = lv.draw_img_dsc_t()
img_draw_dsc.init()
img_draw_dsc.recolor = lv.color_black()
if obj.get_selected_btn() == dsc.id:
img_draw_dsc.recolor_opa = lv.OPA._30
dsc.draw_ctx.img(img_draw_dsc, a, img_star_argb)
#
# Add custom drawer to the button matrix to c
#
btnm = lv.btnmatrix(lv.scr_act())
btnm.add_event_cb(event_cb, lv.EVENT.ALL, None)
btnm.center()
Pagination¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_BTNMATRIX && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
uint32_t id = lv_btnmatrix_get_selected_btn(obj);
bool prev = id == 0 ? true : false;
bool next = id == 6 ? true : false;
if(prev || next) {
/*Find the checked button*/
uint32_t i;
for(i = 1; i < 7; i++) {
if(lv_btnmatrix_has_btn_ctrl(obj, i, LV_BTNMATRIX_CTRL_CHECKED)) break;
}
if(prev && i > 1) i--;
else if(next && i < 5) i++;
lv_btnmatrix_set_btn_ctrl(obj, i, LV_BTNMATRIX_CTRL_CHECKED);
}
}
/**
* Make a button group (pagination)
*/
void lv_example_btnmatrix_3(void)
{
static lv_style_t style_bg;
lv_style_init(&style_bg);
lv_style_set_pad_all(&style_bg, 0);
lv_style_set_pad_gap(&style_bg, 0);
lv_style_set_clip_corner(&style_bg, true);
lv_style_set_radius(&style_bg, LV_RADIUS_CIRCLE);
lv_style_set_border_width(&style_bg, 0);
static lv_style_t style_btn;
lv_style_init(&style_btn);
lv_style_set_radius(&style_btn, 0);
lv_style_set_border_width(&style_btn, 1);
lv_style_set_border_opa(&style_btn, LV_OPA_50);
lv_style_set_border_color(&style_btn, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_border_side(&style_btn, LV_BORDER_SIDE_INTERNAL);
lv_style_set_radius(&style_btn, 0);
static const char * map[] = {LV_SYMBOL_LEFT, "1", "2", "3", "4", "5", LV_SYMBOL_RIGHT, ""};
lv_obj_t * btnm = lv_btnmatrix_create(lv_scr_act());
lv_btnmatrix_set_map(btnm, map);
lv_obj_add_style(btnm, &style_bg, 0);
lv_obj_add_style(btnm, &style_btn, LV_PART_ITEMS);
lv_obj_add_event_cb(btnm, event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_size(btnm, 225, 35);
/*Allow selecting on one number at time*/
lv_btnmatrix_set_btn_ctrl_all(btnm, LV_BTNMATRIX_CTRL_CHECKABLE);
lv_btnmatrix_clear_btn_ctrl(btnm, 0, LV_BTNMATRIX_CTRL_CHECKABLE);
lv_btnmatrix_clear_btn_ctrl(btnm, 6, LV_BTNMATRIX_CTRL_CHECKABLE);
lv_btnmatrix_set_one_checked(btnm, true);
lv_btnmatrix_set_btn_ctrl(btnm, 1, LV_BTNMATRIX_CTRL_CHECKED);
lv_obj_center(btnm);
}
#endif
def event_cb(e):
obj = e.get_target()
id = obj.get_selected_btn()
if id == 0:
prev = True
else:
prev = False
if id == 6:
next = True
else:
next = False
if prev or next:
# Find the checked butto
for i in range(7):
if obj.has_btn_ctrl(i, lv.btnmatrix.CTRL.CHECKED):
break
if prev and i > 1:
i-=1
elif next and i < 5:
i+=1
obj.set_btn_ctrl(i, lv.btnmatrix.CTRL.CHECKED)
#
# Make a button group
#
style_bg = lv.style_t()
style_bg.init()
style_bg.set_pad_all(0)
style_bg.set_pad_gap(0)
style_bg.set_clip_corner(True)
style_bg.set_radius(lv.RADIUS.CIRCLE)
style_bg.set_border_width(0)
style_btn = lv.style_t()
style_btn.init()
style_btn.set_radius(0)
style_btn.set_border_width(1)
style_btn.set_border_opa(lv.OPA._50)
style_btn.set_border_color(lv.palette_main(lv.PALETTE.GREY))
style_btn.set_border_side(lv.BORDER_SIDE.INTERNAL)
style_btn.set_radius(0)
map = [lv.SYMBOL.LEFT,"1","2", "3", "4", "5",lv.SYMBOL.RIGHT, ""]
btnm = lv.btnmatrix(lv.scr_act())
btnm.set_map(map)
btnm.add_style(style_bg, 0)
btnm.add_style(style_btn, lv.PART.ITEMS)
btnm.add_event_cb(event_cb, lv.EVENT.VALUE_CHANGED, None)
btnm.set_size(225, 35)
# Allow selecting on one number at time
btnm.set_btn_ctrl_all(lv.btnmatrix.CTRL.CHECKABLE)
btnm.clear_btn_ctrl(0, lv.btnmatrix.CTRL.CHECKABLE)
btnm.clear_btn_ctrl(6, lv.btnmatrix.CTRL.CHECKABLE)
btnm.set_one_checked(True)
btnm.set_btn_ctrl(1, lv.btnmatrix.CTRL.CHECKED)
btnm.center()
Calendar¶
Calendar with header¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CALENDAR && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_current_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_calendar_date_t date;
if(lv_calendar_get_pressed_date(obj, &date)) {
LV_LOG_USER("Clicked date: %02d.%02d.%d", date.day, date.month, date.year);
}
}
}
void lv_example_calendar_1(void)
{
lv_obj_t * calendar = lv_calendar_create(lv_scr_act());
lv_obj_set_size(calendar, 185, 185);
lv_obj_align(calendar, LV_ALIGN_CENTER, 0, 27);
lv_obj_add_event_cb(calendar, event_handler, LV_EVENT_ALL, NULL);
lv_calendar_set_today_date(calendar, 2021, 02, 23);
lv_calendar_set_showed_date(calendar, 2021, 02);
/*Highlight a few days*/
static lv_calendar_date_t highlighted_days[3]; /*Only its pointer will be saved so should be static*/
highlighted_days[0].year = 2021;
highlighted_days[0].month = 02;
highlighted_days[0].day = 6;
highlighted_days[1].year = 2021;
highlighted_days[1].month = 02;
highlighted_days[1].day = 11;
highlighted_days[2].year = 2022;
highlighted_days[2].month = 02;
highlighted_days[2].day = 22;
lv_calendar_set_highlighted_dates(calendar, highlighted_days, 3);
#if LV_USE_CALENDAR_HEADER_DROPDOWN
lv_calendar_header_dropdown_create(calendar);
#elif LV_USE_CALENDAR_HEADER_ARROW
lv_calendar_header_arrow_create(calendar);
#endif
lv_calendar_set_showed_date(calendar, 2021, 10);
}
#endif
def event_handler(evt):
code = evt.get_code()
if code == lv.EVENT.VALUE_CHANGED:
source = evt.get_current_target()
date = lv.calendar_date_t()
if source.get_pressed_date(date) == lv.RES.OK:
calendar.set_today_date(date.year, date.month, date.day)
print("Clicked date: %02d.%02d.%02d"%(date.day, date.month, date.year))
calendar = lv.calendar(lv.scr_act())
calendar.set_size(200, 200)
calendar.align(lv.ALIGN.CENTER, 0, 20)
calendar.add_event_cb(event_handler, lv.EVENT.ALL, None)
calendar.set_today_date(2021, 02, 23)
calendar.set_showed_date(2021, 02)
# Highlight a few days
highlighted_days=[
lv.calendar_date_t({'year':2021, 'month':2, 'day':6}),
lv.calendar_date_t({'year':2021, 'month':2, 'day':11}),
lv.calendar_date_t({'year':2021, 'month':2, 'day':22})
]
calendar.set_highlighted_dates(highlighted_days, len(highlighted_days))
lv.calendar_header_dropdown(calendar)
Canvas¶
Drawing on the Canvas and rotate¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 200
#define CANVAS_HEIGHT 150
void lv_example_canvas_1(void)
{
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.radius = 10;
rect_dsc.bg_opa = LV_OPA_COVER;
rect_dsc.bg_grad.dir = LV_GRAD_DIR_HOR;
rect_dsc.bg_grad.stops[0].color = lv_palette_main(LV_PALETTE_RED);
rect_dsc.bg_grad.stops[1].color = lv_palette_main(LV_PALETTE_BLUE);
rect_dsc.border_width = 2;
rect_dsc.border_opa = LV_OPA_90;
rect_dsc.border_color = lv_color_white();
rect_dsc.shadow_width = 5;
rect_dsc.shadow_ofs_x = 5;
rect_dsc.shadow_ofs_y = 5;
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.color = lv_palette_main(LV_PALETTE_ORANGE);
static lv_color_t cbuf[LV_CANVAS_BUF_SIZE_TRUE_COLOR(CANVAS_WIDTH, CANVAS_HEIGHT)];
lv_obj_t * canvas = lv_canvas_create(lv_scr_act());
lv_canvas_set_buffer(canvas, cbuf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_IMG_CF_TRUE_COLOR);
lv_obj_center(canvas);
lv_canvas_fill_bg(canvas, lv_palette_lighten(LV_PALETTE_GREY, 3), LV_OPA_COVER);
lv_canvas_draw_rect(canvas, 70, 60, 100, 70, &rect_dsc);
lv_canvas_draw_text(canvas, 40, 20, 100, &label_dsc, "Some text on text canvas");
/*Test the rotation. It requires another buffer where the original image is stored.
*So copy the current image to buffer and rotate it to the canvas*/
static lv_color_t cbuf_tmp[CANVAS_WIDTH * CANVAS_HEIGHT];
memcpy(cbuf_tmp, cbuf, sizeof(cbuf_tmp));
lv_img_dsc_t img;
img.data = (void *)cbuf_tmp;
img.header.cf = LV_IMG_CF_TRUE_COLOR;
img.header.w = CANVAS_WIDTH;
img.header.h = CANVAS_HEIGHT;
lv_canvas_fill_bg(canvas, lv_palette_lighten(LV_PALETTE_GREY, 3), LV_OPA_COVER);
lv_canvas_transform(canvas, &img, 120, LV_IMG_ZOOM_NONE, 0, 0, CANVAS_WIDTH / 2, CANVAS_HEIGHT / 2, true);
}
#endif
_CANVAS_WIDTH = 200
_CANVAS_HEIGHT = 150
LV_IMG_ZOOM_NONE = 256
rect_dsc = lv.draw_rect_dsc_t()
rect_dsc.init()
rect_dsc.radius = 10
rect_dsc.bg_opa = lv.OPA.COVER
rect_dsc.bg_grad.dir = lv.GRAD_DIR.HOR
rect_dsc.bg_grad.stops[0].color = lv.palette_main(lv.PALETTE.RED)
rect_dsc.bg_grad.stops[1].color = lv.palette_main(lv.PALETTE.BLUE)
rect_dsc.border_width = 2
rect_dsc.border_opa = lv.OPA._90
rect_dsc.border_color = lv.color_white()
rect_dsc.shadow_width = 5
rect_dsc.shadow_ofs_x = 5
rect_dsc.shadow_ofs_y = 5
label_dsc = lv.draw_label_dsc_t()
label_dsc.init()
label_dsc.color = lv.palette_main(lv.PALETTE.YELLOW)
cbuf = bytearray(_CANVAS_WIDTH * _CANVAS_HEIGHT * 4)
canvas = lv.canvas(lv.scr_act())
canvas.set_buffer(cbuf, _CANVAS_WIDTH, _CANVAS_HEIGHT, lv.img.CF.TRUE_COLOR)
canvas.center()
canvas.fill_bg(lv.palette_lighten(lv.PALETTE.GREY, 3), lv.OPA.COVER)
canvas.draw_rect(70, 60, 100, 70, rect_dsc)
canvas.draw_text(40, 20, 100, label_dsc, "Some text on text canvas")
# Test the rotation. It requires another buffer where the original image is stored.
# So copy the current image to buffer and rotate it to the canvas
img = lv.img_dsc_t()
img.data = cbuf[:]
img.header.cf = lv.img.CF.TRUE_COLOR
img.header.w = _CANVAS_WIDTH
img.header.h = _CANVAS_HEIGHT
canvas.fill_bg(lv.palette_lighten(lv.PALETTE.GREY, 3), lv.OPA.COVER)
canvas.transform(img, 30, LV_IMG_ZOOM_NONE, 0, 0, _CANVAS_WIDTH // 2, _CANVAS_HEIGHT // 2, True)
Transparent Canvas with chroma keying¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Create a transparent canvas with Chroma keying and indexed color format (palette).
*/
void lv_example_canvas_2(void)
{
/*Create a button to better see the transparency*/
lv_btn_create(lv_scr_act());
/*Create a buffer for the canvas*/
static lv_color_t cbuf[LV_CANVAS_BUF_SIZE_INDEXED_1BIT(CANVAS_WIDTH, CANVAS_HEIGHT)];
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_scr_act());
lv_canvas_set_buffer(canvas, cbuf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_IMG_CF_INDEXED_1BIT);
lv_canvas_set_palette(canvas, 0, LV_COLOR_CHROMA_KEY);
lv_canvas_set_palette(canvas, 1, lv_palette_main(LV_PALETTE_RED));
/*Create colors with the indices of the palette*/
lv_color_t c0;
lv_color_t c1;
c0.full = 0;
c1.full = 1;
/*Red background (There is no dedicated alpha channel in indexed images so LV_OPA_COVER is ignored)*/
lv_canvas_fill_bg(canvas, c1, LV_OPA_COVER);
/*Create hole on the canvas*/
uint32_t x;
uint32_t y;
for(y = 10; y < 30; y++) {
for(x = 5; x < 20; x++) {
lv_canvas_set_px_color(canvas, x, y, c0);
}
}
}
#endif
CANVAS_WIDTH = 50
CANVAS_HEIGHT = 50
LV_COLOR_CHROMA_KEY = lv.color_hex(0x00ff00)
def LV_IMG_BUF_SIZE_ALPHA_1BIT(w, h):
return int(((w / 8) + 1) * h)
def LV_IMG_BUF_SIZE_INDEXED_1BIT(w, h):
return LV_IMG_BUF_SIZE_ALPHA_1BIT(w, h) + 4 * 2
def LV_CANVAS_BUF_SIZE_INDEXED_1BIT(w, h):
return LV_IMG_BUF_SIZE_INDEXED_1BIT(w, h)
#
# Create a transparent canvas with Chroma keying and indexed color format (palette).
#
# Create a button to better see the transparency
btn=lv.btn(lv.scr_act())
# Create a buffer for the canvas
cbuf= bytearray(LV_CANVAS_BUF_SIZE_INDEXED_1BIT(CANVAS_WIDTH, CANVAS_HEIGHT))
# Create a canvas and initialize its palette
canvas = lv.canvas(lv.scr_act())
canvas.set_buffer(cbuf, CANVAS_WIDTH, CANVAS_HEIGHT, lv.img.CF.INDEXED_1BIT)
canvas.set_palette(0, LV_COLOR_CHROMA_KEY)
canvas.set_palette(1, lv.palette_main(lv.PALETTE.RED))
# Create colors with the indices of the palette
c0 = lv.color_t()
c1 = lv.color_t()
c0.full = 0
c1.full = 1
# Red background (There is no dedicated alpha channel in indexed images so LV_OPA_COVER is ignored)
canvas.fill_bg(c1, lv.OPA.COVER)
# Create hole on the canvas
for y in range(10,30):
for x in range(5,20):
canvas.set_px(x, y, c0)
Chart¶
Line Chart¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
void lv_example_chart_1(void)
{
/*Create a chart*/
lv_obj_t * chart;
chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_center(chart);
lv_chart_set_type(chart, LV_CHART_TYPE_LINE); /*Show lines and points too*/
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_GREEN), LV_CHART_AXIS_SECONDARY_Y);
/*Set the next points on 'ser1'*/
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 30);
lv_chart_set_next_value(chart, ser1, 70);
lv_chart_set_next_value(chart, ser1, 90);
/*Directly set points on 'ser2'*/
ser2->y_points[0] = 90;
ser2->y_points[1] = 70;
ser2->y_points[2] = 65;
ser2->y_points[3] = 65;
ser2->y_points[4] = 65;
ser2->y_points[5] = 65;
ser2->y_points[6] = 65;
ser2->y_points[7] = 65;
ser2->y_points[8] = 65;
ser2->y_points[9] = 65;
lv_chart_refresh(chart); /*Required after direct set*/
}
#endif
# Create a chart
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.center()
chart.set_type(lv.chart.TYPE.LINE) # Show lines and points too
# Add two data series
ser1 = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
ser2 = chart.add_series(lv.palette_main(lv.PALETTE.GREEN), lv.chart.AXIS.SECONDARY_Y)
print(ser2)
# Set next points on ser1
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,10)
chart.set_next_value(ser1,30)
chart.set_next_value(ser1,70)
chart.set_next_value(ser1,90)
# Directly set points on 'ser2'
ser2.y_points = [90, 70, 65, 65, 65, 65, 65, 65, 65, 65]
chart.refresh() # Required after direct set
Faded area line chart with custom division lines¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_DRAW_COMPLEX && LV_BUILD_EXAMPLES
static lv_obj_t * chart1;
static lv_chart_series_t * ser1;
static lv_chart_series_t * ser2;
static void draw_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
/*Add the faded area before the lines are drawn*/
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(dsc->part == LV_PART_ITEMS) {
if(!dsc->p1 || !dsc->p2) return;
/*Add a line mask that keeps the area below the line*/
lv_draw_mask_line_param_t line_mask_param;
lv_draw_mask_line_points_init(&line_mask_param, dsc->p1->x, dsc->p1->y, dsc->p2->x, dsc->p2->y,
LV_DRAW_MASK_LINE_SIDE_BOTTOM);
int16_t line_mask_id = lv_draw_mask_add(&line_mask_param, NULL);
/*Add a fade effect: transparent bottom covering top*/
lv_coord_t h = lv_obj_get_height(obj);
lv_draw_mask_fade_param_t fade_mask_param;
lv_draw_mask_fade_init(&fade_mask_param, &obj->coords, LV_OPA_COVER, obj->coords.y1 + h / 8, LV_OPA_TRANSP,
obj->coords.y2);
int16_t fade_mask_id = lv_draw_mask_add(&fade_mask_param, NULL);
/*Draw a rectangle that will be affected by the mask*/
lv_draw_rect_dsc_t draw_rect_dsc;
lv_draw_rect_dsc_init(&draw_rect_dsc);
draw_rect_dsc.bg_opa = LV_OPA_20;
draw_rect_dsc.bg_color = dsc->line_dsc->color;
lv_area_t a;
a.x1 = dsc->p1->x;
a.x2 = dsc->p2->x - 1;
a.y1 = LV_MIN(dsc->p1->y, dsc->p2->y);
a.y2 = obj->coords.y2;
lv_draw_rect(dsc->draw_ctx, &draw_rect_dsc, &a);
/*Remove the masks*/
lv_draw_mask_free_param(&line_mask_param);
lv_draw_mask_free_param(&fade_mask_param);
lv_draw_mask_remove_id(line_mask_id);
lv_draw_mask_remove_id(fade_mask_id);
}
/*Hook the division lines too*/
else if(dsc->part == LV_PART_MAIN) {
if(dsc->line_dsc == NULL || dsc->p1 == NULL || dsc->p2 == NULL) return;
/*Vertical line*/
if(dsc->p1->x == dsc->p2->x) {
dsc->line_dsc->color = lv_palette_lighten(LV_PALETTE_GREY, 1);
if(dsc->id == 3) {
dsc->line_dsc->width = 2;
dsc->line_dsc->dash_gap = 0;
dsc->line_dsc->dash_width = 0;
}
else {
dsc->line_dsc->width = 1;
dsc->line_dsc->dash_gap = 6;
dsc->line_dsc->dash_width = 6;
}
}
/*Horizontal line*/
else {
if(dsc->id == 2) {
dsc->line_dsc->width = 2;
dsc->line_dsc->dash_gap = 0;
dsc->line_dsc->dash_width = 0;
}
else {
dsc->line_dsc->width = 2;
dsc->line_dsc->dash_gap = 6;
dsc->line_dsc->dash_width = 6;
}
if(dsc->id == 1 || dsc->id == 3) {
dsc->line_dsc->color = lv_palette_main(LV_PALETTE_GREEN);
}
else {
dsc->line_dsc->color = lv_palette_lighten(LV_PALETTE_GREY, 1);
}
}
}
}
static void add_data(lv_timer_t * timer)
{
LV_UNUSED(timer);
static uint32_t cnt = 0;
lv_chart_set_next_value(chart1, ser1, lv_rand(20, 90));
if(cnt % 4 == 0) lv_chart_set_next_value(chart1, ser2, lv_rand(40, 60));
cnt++;
}
/**
* Add a faded area effect to the line chart and make some division lines ticker
*/
void lv_example_chart_2(void)
{
/*Create a chart1*/
chart1 = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart1, 200, 150);
lv_obj_center(chart1);
lv_chart_set_type(chart1, LV_CHART_TYPE_LINE); /*Show lines and points too*/
lv_chart_set_div_line_count(chart1, 5, 7);
lv_obj_add_event_cb(chart1, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
lv_chart_set_update_mode(chart1, LV_CHART_UPDATE_MODE_CIRCULAR);
/*Add two data series*/
ser1 = lv_chart_add_series(chart1, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
ser2 = lv_chart_add_series(chart1, lv_palette_main(LV_PALETTE_BLUE), LV_CHART_AXIS_SECONDARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart1, ser1, lv_rand(20, 90));
lv_chart_set_next_value(chart1, ser2, lv_rand(30, 70));
}
lv_timer_create(add_data, 200, NULL);
}
#endif
def draw_event_cb(e):
obj = e.get_target()
# Add the faded area before the lines are drawn
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
if dsc.part != lv.PART.ITEMS:
return
if not dsc.p1 or not dsc.p2:
return
# Add a line mask that keeps the area below the line
line_mask_param = lv.draw_mask_line_param_t()
line_mask_param.points_init(dsc.p1.x, dsc.p1.y, dsc.p2.x, dsc.p2.y, lv.DRAW_MASK_LINE_SIDE.BOTTOM)
# line_mask_id = line_mask_param.draw_mask_add(None)
line_mask_id = lv.draw_mask_add(line_mask_param, None)
# Add a fade effect: transparent bottom covering top
h = obj.get_height()
fade_mask_param = lv.draw_mask_fade_param_t()
coords = lv.area_t()
obj.get_coords(coords)
fade_mask_param.init(coords, lv.OPA.COVER, coords.y1 + h // 8, lv.OPA.TRANSP,coords.y2)
fade_mask_id = lv.draw_mask_add(fade_mask_param,None)
# Draw a rectangle that will be affected by the mask
draw_rect_dsc = lv.draw_rect_dsc_t()
draw_rect_dsc.init()
draw_rect_dsc.bg_opa = lv.OPA._20
draw_rect_dsc.bg_color = dsc.line_dsc.color
a = lv.area_t()
a.x1 = dsc.p1.x
a.x2 = dsc.p2.x - 1
a.y1 = min(dsc.p1.y, dsc.p2.y)
coords = lv.area_t()
obj.get_coords(coords)
a.y2 = coords.y2
dsc.draw_ctx.rect(draw_rect_dsc, a)
# Remove the masks
lv.draw_mask_remove_id(line_mask_id)
lv.draw_mask_remove_id(fade_mask_id)
def add_data(timer):
# LV_UNUSED(timer);
cnt = 0
chart1.set_next_value(ser1, lv.rand(20, 90))
if cnt % 4 == 0:
chart1.set_next_value(ser2, lv.rand(40, 60))
cnt +=1
#
# Add a faded area effect to the line chart
#
# Create a chart1
chart1 = lv.chart(lv.scr_act())
chart1.set_size(200, 150)
chart1.center()
chart1.set_type(lv.chart.TYPE.LINE) # Show lines and points too
chart1.add_event_cb(draw_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
chart1.set_update_mode(lv.chart.UPDATE_MODE.CIRCULAR)
# Add two data series
ser1 = chart1.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
ser2 = chart1.add_series(lv.palette_main(lv.PALETTE.BLUE), lv.chart.AXIS.SECONDARY_Y)
for i in range(10):
chart1.set_next_value(ser1, lv.rand(20, 90))
chart1.set_next_value(ser2, lv.rand(30, 70))
timer = lv.timer_create(add_data, 200, None)
Axis ticks and labels with scrolling¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static void draw_event_cb(lv_event_t * e)
{
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(!lv_obj_draw_part_check_type(dsc, &lv_chart_class, LV_CHART_DRAW_PART_TICK_LABEL)) return;
if(dsc->id == LV_CHART_AXIS_PRIMARY_X && dsc->text) {
const char * month[] = {"Jan", "Febr", "March", "Apr", "May", "Jun", "July", "Aug", "Sept", "Oct", "Nov", "Dec"};
lv_snprintf(dsc->text, dsc->text_length, "%s", month[dsc->value]);
}
}
/**
* Add ticks and labels to the axis and demonstrate scrolling
*/
void lv_example_chart_3(void)
{
/*Create a chart*/
lv_obj_t * chart;
chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_center(chart);
lv_chart_set_type(chart, LV_CHART_TYPE_BAR);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, 0, 100);
lv_chart_set_range(chart, LV_CHART_AXIS_SECONDARY_Y, 0, 400);
lv_chart_set_point_count(chart, 12);
lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
/*Add ticks and label to every axis*/
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_X, 10, 5, 12, 3, true, 40);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_Y, 10, 5, 6, 2, true, 50);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_SECONDARY_Y, 10, 5, 3, 4, true, 50);
/*Zoom in a little in X*/
lv_chart_set_zoom_x(chart, 800);
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_lighten(LV_PALETTE_GREEN, 2), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_darken(LV_PALETTE_GREEN, 2),
LV_CHART_AXIS_SECONDARY_Y);
/*Set the next points on 'ser1'*/
lv_chart_set_next_value(chart, ser1, 31);
lv_chart_set_next_value(chart, ser1, 66);
lv_chart_set_next_value(chart, ser1, 10);
lv_chart_set_next_value(chart, ser1, 89);
lv_chart_set_next_value(chart, ser1, 63);
lv_chart_set_next_value(chart, ser1, 56);
lv_chart_set_next_value(chart, ser1, 32);
lv_chart_set_next_value(chart, ser1, 35);
lv_chart_set_next_value(chart, ser1, 57);
lv_chart_set_next_value(chart, ser1, 85);
lv_chart_set_next_value(chart, ser1, 22);
lv_chart_set_next_value(chart, ser1, 58);
lv_coord_t * ser2_array = lv_chart_get_y_array(chart, ser2);
/*Directly set points on 'ser2'*/
ser2_array[0] = 92;
ser2_array[1] = 71;
ser2_array[2] = 61;
ser2_array[3] = 15;
ser2_array[4] = 21;
ser2_array[5] = 35;
ser2_array[6] = 35;
ser2_array[7] = 58;
ser2_array[8] = 31;
ser2_array[9] = 53;
ser2_array[10] = 33;
ser2_array[11] = 73;
lv_chart_refresh(chart); /*Required after direct set*/
}
#endif
def draw_event_cb(e):
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
if dsc.part == lv.PART.TICKS and dsc.id == lv.chart.AXIS.PRIMARY_X:
month = ["Jan", "Febr", "March", "Apr", "May", "Jun", "July", "Aug", "Sept", "Oct", "Nov", "Dec"]
# dsc.text is defined char text[16], I must therefore convert the Python string to a byte_array
dsc.text = bytes(month[dsc.value],"ascii")
#
# Add ticks and labels to the axis and demonstrate scrolling
#
# Create a chart
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.center()
chart.set_type(lv.chart.TYPE.BAR)
chart.set_range(lv.chart.AXIS.PRIMARY_Y, 0, 100)
chart.set_range(lv.chart.AXIS.SECONDARY_Y, 0, 400)
chart.set_point_count(12)
chart.add_event_cb(draw_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
# Add ticks and label to every axis
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_X, 10, 5, 12, 3, True, 40)
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_Y, 10, 5, 6, 2, True, 50)
chart.set_axis_tick(lv.chart.AXIS.SECONDARY_Y, 10, 5, 3, 4,True, 50)
# Zoom in a little in X
chart.set_zoom_x(800)
# Add two data series
ser1 = lv.chart.add_series(chart, lv.palette_lighten(lv.PALETTE.GREEN, 2), lv.chart.AXIS.PRIMARY_Y)
ser2 = lv.chart.add_series(chart, lv.palette_darken(lv.PALETTE.GREEN, 2), lv.chart.AXIS.SECONDARY_Y)
# Set the next points on 'ser1'
chart.set_next_value(ser1, 31)
chart.set_next_value(ser1, 66)
chart.set_next_value(ser1, 10)
chart.set_next_value(ser1, 89)
chart.set_next_value(ser1, 63)
chart.set_next_value(ser1, 56)
chart.set_next_value(ser1, 32)
chart.set_next_value(ser1, 35)
chart.set_next_value(ser1, 57)
chart.set_next_value(ser1, 85)
chart.set_next_value(ser1, 22)
chart.set_next_value(ser1, 58)
# Directly set points on 'ser2'
ser2.y_points = [92,71,61,15,21,35,35,58,31,53,33,73]
chart.refresh() # Required after direct set
Show the value of the pressed points¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * chart = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_obj_invalidate(chart);
}
if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
lv_coord_t * s = lv_event_get_param(e);
*s = LV_MAX(*s, 20);
}
else if(code == LV_EVENT_DRAW_POST_END) {
int32_t id = lv_chart_get_pressed_point(chart);
if(id == LV_CHART_POINT_NONE) return;
LV_LOG_USER("Selected point %d", (int)id);
lv_chart_series_t * ser = lv_chart_get_series_next(chart, NULL);
while(ser) {
lv_point_t p;
lv_chart_get_point_pos_by_id(chart, ser, id, &p);
lv_coord_t * y_array = lv_chart_get_y_array(chart, ser);
lv_coord_t value = y_array[id];
char buf[16];
lv_snprintf(buf, sizeof(buf), LV_SYMBOL_DUMMY"$%d", value);
lv_draw_rect_dsc_t draw_rect_dsc;
lv_draw_rect_dsc_init(&draw_rect_dsc);
draw_rect_dsc.bg_color = lv_color_black();
draw_rect_dsc.bg_opa = LV_OPA_50;
draw_rect_dsc.radius = 3;
draw_rect_dsc.bg_img_src = buf;
draw_rect_dsc.bg_img_recolor = lv_color_white();
lv_area_t a;
a.x1 = chart->coords.x1 + p.x - 20;
a.x2 = chart->coords.x1 + p.x + 20;
a.y1 = chart->coords.y1 + p.y - 30;
a.y2 = chart->coords.y1 + p.y - 10;
lv_draw_ctx_t * draw_ctx = lv_event_get_draw_ctx(e);
lv_draw_rect(draw_ctx, &draw_rect_dsc, &a);
ser = lv_chart_get_series_next(chart, ser);
}
}
else if(code == LV_EVENT_RELEASED) {
lv_obj_invalidate(chart);
}
}
/**
* Show the value of the pressed points
*/
void lv_example_chart_4(void)
{
/*Create a chart*/
lv_obj_t * chart;
chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_center(chart);
lv_obj_add_event_cb(chart, event_cb, LV_EVENT_ALL, NULL);
lv_obj_refresh_ext_draw_size(chart);
/*Zoom in a little in X*/
lv_chart_set_zoom_x(chart, 800);
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_GREEN), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart, ser1, lv_rand(60, 90));
lv_chart_set_next_value(chart, ser2, lv_rand(10, 40));
}
}
#endif
def event_cb(e):
code = e.get_code()
chart = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
chart.invalidate()
if code == lv.EVENT.REFR_EXT_DRAW_SIZE:
e.set_ext_draw_size(20)
elif code == lv.EVENT.DRAW_POST_END:
id = lv.chart.get_pressed_point(chart)
if id == lv.CHART_POINT.NONE:
return
# print("Selected point ", id)
for i in range(len(series)):
p = lv.point_t()
chart.get_point_pos_by_id(series[i], id, p)
value = series_points[i][id]
buf = lv.SYMBOL.DUMMY + "$" + str(value)
draw_rect_dsc = lv.draw_rect_dsc_t()
draw_rect_dsc.init()
draw_rect_dsc.bg_color = lv.color_black()
draw_rect_dsc.bg_opa = lv.OPA._50
draw_rect_dsc.radius = 3
draw_rect_dsc.bg_img_src = buf
draw_rect_dsc.bg_img_recolor = lv.color_white()
a = lv.area_t()
coords = lv.area_t()
chart.get_coords(coords)
a.x1 = coords.x1 + p.x - 20
a.x2 = coords.x1 + p.x + 20
a.y1 = coords.y1 + p.y - 30
a.y2 = coords.y1 + p.y - 10
clip_area = lv.area_t.__cast__(e.get_param())
lv.draw_rect(a, clip_area, draw_rect_dsc)
elif code == lv.EVENT.RELEASED:
chart.invalidate()
#
# Add ticks and labels to the axis and demonstrate scrolling
#
# Create a chart
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.center()
chart.add_event_cb(event_cb, lv.EVENT.ALL, None)
chart.refresh_ext_draw_size()
# Zoom in a little in X
chart.set_zoom_x(800)
# Add two data series
ser1 = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
ser2 = chart.add_series(lv.palette_main(lv.PALETTE.GREEN), lv.chart.AXIS.PRIMARY_Y)
ser1_p = []
ser2_p = []
for i in range(10):
ser1_p.append(lv.rand(60,90))
ser2_p.append(lv.rand(10,40))
ser1.y_points = ser1_p
ser2.y_points = ser2_p
series = [ser1,ser2]
series_points=[ser1_p,ser2_p]
Display 1000 data points with zooming and scrolling¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_USE_SLIDER && LV_BUILD_EXAMPLES
static lv_obj_t * chart;
/* Source: https://github.com/ankur219/ECG-Arrhythmia-classification/blob/642230149583adfae1e4bd26c6f0e1fd8af2be0e/sample.csv*/
static const lv_coord_t ecg_sample[] = {
-2, 2, 0, -15, -39, -63, -71, -68, -67, -69, -84, -95, -104, -107, -108, -107, -107, -107, -107, -114, -118, -117,
-112, -100, -89, -83, -71, -64, -58, -58, -62, -62, -58, -51, -46, -39, -27, -10, 4, 7, 1, -3, 0, 14, 24, 30, 25, 19,
13, 7, 12, 15, 18, 21, 13, 6, 9, 8, 17, 19, 13, 11, 11, 11, 23, 30, 37, 34, 25, 14, 15, 19, 28, 31, 26, 23, 25, 31,
39, 37, 37, 34, 30, 32, 22, 29, 31, 33, 37, 23, 13, 7, 2, 4, -2, 2, 11, 22, 33, 19, -1, -27, -55, -67, -72, -71, -63,
-49, -18, 35, 113, 230, 369, 525, 651, 722, 730, 667, 563, 454, 357, 305, 288, 274, 255, 212, 173, 143, 117, 82, 39,
-13, -53, -78, -91, -101, -113, -124, -131, -131, -131, -129, -128, -129, -125, -123, -123, -129, -139, -148, -153,
-159, -166, -183, -205, -227, -243, -248, -246, -254, -280, -327, -381, -429, -473, -517, -556, -592, -612, -620,
-620, -614, -604, -591, -574, -540, -497, -441, -389, -358, -336, -313, -284, -222, -167, -114, -70, -47, -28, -4, 12,
38, 52, 58, 56, 56, 57, 68, 77, 86, 86, 80, 69, 67, 70, 82, 85, 89, 90, 89, 89, 88, 91, 96, 97, 91, 83, 78, 82, 88, 95,
96, 105, 106, 110, 102, 100, 96, 98, 97, 101, 98, 99, 100, 107, 113, 119, 115, 110, 96, 85, 73, 64, 69, 76, 79,
78, 75, 85, 100, 114, 113, 105, 96, 84, 74, 66, 60, 75, 85, 89, 83, 67, 61, 67, 73, 79, 74, 63, 57, 56, 58, 61, 55,
48, 45, 46, 55, 62, 55, 49, 43, 50, 59, 63, 57, 40, 31, 23, 25, 27, 31, 35, 34, 30, 36, 34, 42, 38, 36, 40, 46, 50,
47, 32, 30, 32, 52, 67, 73, 71, 63, 54, 53, 45, 41, 28, 13, 3, 1, 4, 4, -8, -23, -32, -31, -19, -5, 3, 9, 13, 19,
24, 27, 29, 25, 22, 26, 32, 42, 51, 56, 60, 57, 55, 53, 53, 54, 59, 54, 49, 26, -3, -11, -20, -47, -100, -194, -236,
-212, -123, 8, 103, 142, 147, 120, 105, 98, 93, 81, 61, 40, 26, 28, 30, 30, 27, 19, 17, 21, 20, 19, 19, 22, 36, 40,
35, 20, 7, 1, 10, 18, 27, 22, 6, -4, -2, 3, 6, -2, -13, -14, -10, -2, 3, 2, -1, -5, -10, -19, -32, -42, -55, -60,
-68, -77, -86, -101, -110, -117, -115, -104, -92, -84, -85, -84, -73, -65, -52, -50, -45, -35, -20, -3, 12, 20, 25,
26, 28, 28, 30, 28, 25, 28, 33, 42, 42, 36, 23, 9, 0, 1, -4, 1, -4, -4, 1, 5, 9, 9, -3, -1, -18, -50, -108, -190,
-272, -340, -408, -446, -537, -643, -777, -894, -920, -853, -697, -461, -251, -60, 58, 103, 129, 139, 155, 170, 173,
178, 185, 190, 193, 200, 208, 215, 225, 224, 232, 234, 240, 240, 236, 229, 226, 224, 232, 233, 232, 224, 219, 219,
223, 231, 226, 223, 219, 218, 223, 223, 223, 233, 245, 268, 286, 296, 295, 283, 271, 263, 252, 243, 226, 210, 197,
186, 171, 152, 133, 117, 114, 110, 107, 96, 80, 63, 48, 40, 38, 34, 28, 15, 2, -7, -11, -14, -18, -29, -37, -44, -50,
-58, -63, -61, -52, -50, -48, -61, -59, -58, -54, -47, -52, -62, -61, -64, -54, -52, -59, -69, -76, -76, -69, -67,
-74, -78, -81, -80, -73, -65, -57, -53, -51, -47, -35, -27, -22, -22, -24, -21, -17, -13, -10, -11, -13, -20, -20,
-12, -2, 7, -1, -12, -16, -13, -2, 2, -4, -5, -2, 9, 19, 19, 14, 11, 13, 19, 21, 20, 18, 19, 19, 19, 16, 15, 13, 14,
9, 3, -5, -9, -5, -3, -2, -3, -3, 2, 8, 9, 9, 5, 6, 8, 8, 7, 4, 3, 4, 5, 3, 5, 5, 13, 13, 12, 10, 10, 15, 22, 17,
14, 7, 10, 15, 16, 11, 12, 10, 13, 9, -2, -4, -2, 7, 16, 16, 17, 16, 7, -1, -16, -18, -16, -9, -4, -5, -10, -9, -8,
-3, -4, -10, -19, -20, -16, -9, -9, -23, -40, -48, -43, -33, -19, -21, -26, -31, -33, -19, 0, 17, 24, 9, -17, -47,
-63, -67, -59, -52, -51, -50, -49, -42, -26, -21, -15, -20, -23, -22, -19, -12, -8, 5, 18, 27, 32, 26, 25, 26, 22,
23, 17, 14, 17, 21, 25, 2, -45, -121, -196, -226, -200, -118, -9, 73, 126, 131, 114, 87, 60, 42, 29, 26, 34, 35, 34,
25, 12, 9, 7, 3, 2, -8, -11, 2, 23, 38, 41, 23, 9, 10, 13, 16, 8, -8, -17, -23, -26, -25, -21, -15, -10, -13, -13,
-19, -22, -29, -40, -48, -48, -54, -55, -66, -82, -85, -90, -92, -98, -114, -119, -124, -129, -132, -146, -146, -138,
-124, -99, -85, -72, -65, -65, -65, -66, -63, -64, -64, -58, -46, -26, -9, 2, 2, 4, 0, 1, 4, 3, 10, 11, 10, 2, -4,
0, 10, 18, 20, 6, 2, -9, -7, -3, -3, -2, -7, -12, -5, 5, 24, 36, 31, 25, 6, 3, 7, 12, 17, 11, 0, -6, -9, -8, -7, -5,
-6, -2, -2, -6, -2, 2, 14, 24, 22, 15, 8, 4, 6, 7, 12, 16, 25, 20, 7, -16, -41, -60, -67, -65, -54, -35, -11, 30,
84, 175, 302, 455, 603, 707, 743, 714, 625, 519, 414, 337, 300, 281, 263, 239, 197, 163, 136, 109, 77, 34, -18, -50,
-66, -74, -79, -92, -107, -117, -127, -129, -135, -139, -141, -155, -159, -167, -171, -169, -174, -175, -178, -191,
-202, -223, -235, -243, -237, -240, -256, -298, -345, -393, -432, -475, -518, -565, -596, -619, -623, -623, -614,
-599, -583, -559, -524, -477, -425, -383, -357, -331, -301, -252, -198, -143, -96, -57, -29, -8, 10, 31, 45, 60, 65,
70, 74, 76, 79, 82, 79, 75, 62,
};
static void slider_x_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
int32_t v = lv_slider_get_value(obj);
lv_chart_set_zoom_x(chart, v);
}
static void slider_y_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
int32_t v = lv_slider_get_value(obj);
lv_chart_set_zoom_y(chart, v);
}
/**
* Display 1000 data points with zooming and scrolling.
* See how the chart changes drawing mode (draw only vertical lines) when
* the points get too crowded.
*/
void lv_example_chart_5(void)
{
/*Create a chart*/
chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, LV_ALIGN_CENTER, -30, -30);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, -1000, 1000);
/*Do not display points on the data*/
lv_obj_set_style_size(chart, 0, LV_PART_INDICATOR);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t pcnt = sizeof(ecg_sample) / sizeof(ecg_sample[0]);
lv_chart_set_point_count(chart, pcnt);
lv_chart_set_ext_y_array(chart, ser, (lv_coord_t *)ecg_sample);
lv_obj_t * slider;
slider = lv_slider_create(lv_scr_act());
lv_slider_set_range(slider, LV_IMG_ZOOM_NONE, LV_IMG_ZOOM_NONE * 10);
lv_obj_add_event_cb(slider, slider_x_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_size(slider, 200, 10);
lv_obj_align_to(slider, chart, LV_ALIGN_OUT_BOTTOM_MID, 0, 20);
slider = lv_slider_create(lv_scr_act());
lv_slider_set_range(slider, LV_IMG_ZOOM_NONE, LV_IMG_ZOOM_NONE * 10);
lv_obj_add_event_cb(slider, slider_y_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_size(slider, 10, 150);
lv_obj_align_to(slider, chart, LV_ALIGN_OUT_RIGHT_MID, 20, 0);
}
#endif
# Source: https://github.com/ankur219/ECG-Arrhythmia-classification/blob/642230149583adfae1e4bd26c6f0e1fd8af2be0e/sample.csv
ecg_sample = [
-2, 2, 0, -15, -39, -63, -71, -68, -67, -69, -84, -95, -104, -107, -108, -107, -107, -107, -107, -114, -118, -117,
-112, -100, -89, -83, -71, -64, -58, -58, -62, -62, -58, -51, -46, -39, -27, -10, 4, 7, 1, -3, 0, 14, 24, 30, 25, 19,
13, 7, 12, 15, 18, 21, 13, 6, 9, 8, 17, 19, 13, 11, 11, 11, 23, 30, 37, 34, 25, 14, 15, 19, 28, 31, 26, 23, 25, 31,
39, 37, 37, 34, 30, 32, 22, 29, 31, 33, 37, 23, 13, 7, 2, 4, -2, 2, 11, 22, 33, 19, -1, -27, -55, -67, -72, -71, -63,
-49, -18, 35, 113, 230, 369, 525, 651, 722, 730, 667, 563, 454, 357, 305, 288, 274, 255, 212, 173, 143, 117, 82, 39,
-13, -53, -78, -91, -101, -113, -124, -131, -131, -131, -129, -128, -129, -125, -123, -123, -129, -139, -148, -153,
-159, -166, -183, -205, -227, -243, -248, -246, -254, -280, -327, -381, -429, -473, -517, -556, -592, -612, -620,
-620, -614, -604, -591, -574, -540, -497, -441, -389, -358, -336, -313, -284, -222, -167, -114, -70, -47, -28, -4, 12,
38, 52, 58, 56, 56, 57, 68, 77, 86, 86, 80, 69, 67, 70, 82, 85, 89, 90, 89, 89, 88, 91, 96, 97, 91, 83, 78, 82, 88, 95,
96, 105, 106, 110, 102, 100, 96, 98, 97, 101, 98, 99, 100, 107, 113, 119, 115, 110, 96, 85, 73, 64, 69, 76, 79,
78, 75, 85, 100, 114, 113, 105, 96, 84, 74, 66, 60, 75, 85, 89, 83, 67, 61, 67, 73, 79, 74, 63, 57, 56, 58, 61, 55,
48, 45, 46, 55, 62, 55, 49, 43, 50, 59, 63, 57, 40, 31, 23, 25, 27, 31, 35, 34, 30, 36, 34, 42, 38, 36, 40, 46, 50,
47, 32, 30, 32, 52, 67, 73, 71, 63, 54, 53, 45, 41, 28, 13, 3, 1, 4, 4, -8, -23, -32, -31, -19, -5, 3, 9, 13, 19,
24, 27, 29, 25, 22, 26, 32, 42, 51, 56, 60, 57, 55, 53, 53, 54, 59, 54, 49, 26, -3, -11, -20, -47, -100, -194, -236,
-212, -123, 8, 103, 142, 147, 120, 105, 98, 93, 81, 61, 40, 26, 28, 30, 30, 27, 19, 17, 21, 20, 19, 19, 22, 36, 40,
35, 20, 7, 1, 10, 18, 27, 22, 6, -4, -2, 3, 6, -2, -13, -14, -10, -2, 3, 2, -1, -5, -10, -19, -32, -42, -55, -60,
-68, -77, -86, -101, -110, -117, -115, -104, -92, -84, -85, -84, -73, -65, -52, -50, -45, -35, -20, -3, 12, 20, 25,
26, 28, 28, 30, 28, 25, 28, 33, 42, 42, 36, 23, 9, 0, 1, -4, 1, -4, -4, 1, 5, 9, 9, -3, -1, -18, -50, -108, -190,
-272, -340, -408, -446, -537, -643, -777, -894, -920, -853, -697, -461, -251, -60, 58, 103, 129, 139, 155, 170, 173,
178, 185, 190, 193, 200, 208, 215, 225, 224, 232, 234, 240, 240, 236, 229, 226, 224, 232, 233, 232, 224, 219, 219,
223, 231, 226, 223, 219, 218, 223, 223, 223, 233, 245, 268, 286, 296, 295, 283, 271, 263, 252, 243, 226, 210, 197,
186, 171, 152, 133, 117, 114, 110, 107, 96, 80, 63, 48, 40, 38, 34, 28, 15, 2, -7, -11, -14, -18, -29, -37, -44, -50,
-58, -63, -61, -52, -50, -48, -61, -59, -58, -54, -47, -52, -62, -61, -64, -54, -52, -59, -69, -76, -76, -69, -67,
-74, -78, -81, -80, -73, -65, -57, -53, -51, -47, -35, -27, -22, -22, -24, -21, -17, -13, -10, -11, -13, -20, -20,
-12, -2, 7, -1, -12, -16, -13, -2, 2, -4, -5, -2, 9, 19, 19, 14, 11, 13, 19, 21, 20, 18, 19, 19, 19, 16, 15, 13, 14,
9, 3, -5, -9, -5, -3, -2, -3, -3, 2, 8, 9, 9, 5, 6, 8, 8, 7, 4, 3, 4, 5, 3, 5, 5, 13, 13, 12, 10, 10, 15, 22, 17,
14, 7, 10, 15, 16, 11, 12, 10, 13, 9, -2, -4, -2, 7, 16, 16, 17, 16, 7, -1, -16, -18, -16, -9, -4, -5, -10, -9, -8,
-3, -4, -10, -19, -20, -16, -9, -9, -23, -40, -48, -43, -33, -19, -21, -26, -31, -33, -19, 0, 17, 24, 9, -17, -47,
-63, -67, -59, -52, -51, -50, -49, -42, -26, -21, -15, -20, -23, -22, -19, -12, -8, 5, 18, 27, 32, 26, 25, 26, 22,
23, 17, 14, 17, 21, 25, 2, -45, -121, -196, -226, -200, -118, -9, 73, 126, 131, 114, 87, 60, 42, 29, 26, 34, 35, 34,
25, 12, 9, 7, 3, 2, -8, -11, 2, 23, 38, 41, 23, 9, 10, 13, 16, 8, -8, -17, -23, -26, -25, -21, -15, -10, -13, -13,
-19, -22, -29, -40, -48, -48, -54, -55, -66, -82, -85, -90, -92, -98, -114, -119, -124, -129, -132, -146, -146, -138,
-124, -99, -85, -72, -65, -65, -65, -66, -63, -64, -64, -58, -46, -26, -9, 2, 2, 4, 0, 1, 4, 3, 10, 11, 10, 2, -4,
0, 10, 18, 20, 6, 2, -9, -7, -3, -3, -2, -7, -12, -5, 5, 24, 36, 31, 25, 6, 3, 7, 12, 17, 11, 0, -6, -9, -8, -7, -5,
-6, -2, -2, -6, -2, 2, 14, 24, 22, 15, 8, 4, 6, 7, 12, 16, 25, 20, 7, -16, -41, -60, -67, -65, -54, -35, -11, 30,
84, 175, 302, 455, 603, 707, 743, 714, 625, 519, 414, 337, 300, 281, 263, 239, 197, 163, 136, 109, 77, 34, -18, -50,
-66, -74, -79, -92, -107, -117, -127, -129, -135, -139, -141, -155, -159, -167, -171, -169, -174, -175, -178, -191,
-202, -223, -235, -243, -237, -240, -256, -298, -345, -393, -432, -475, -518, -565, -596, -619, -623, -623, -614,
-599, -583, -559, -524, -477, -425, -383, -357, -331, -301, -252, -198, -143, -96, -57, -29, -8, 10, 31, 45, 60, 65,
70, 74, 76, 79, 82, 79, 75, 62,
]
def slider_x_event_cb(e):
slider = e.get_target()
v = slider.get_value()
chart.set_zoom_x(v)
def slider_y_event_cb(e):
slider = e.get_target()
v = slider.get_value()
chart.set_zoom_y(v)
#
# Display 1000 data points with zooming and scrolling.
# See how the chart changes drawing mode (draw only vertical lines) when
# the points get too crowded.
# Create a chart
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.align(lv.ALIGN.CENTER, -30, -30)
chart.set_range(lv.chart.AXIS.PRIMARY_Y, -1000, 1000)
# Do not display points on the data
chart.set_style_size(0, lv.PART.INDICATOR)
ser = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
pcnt = len(ecg_sample)
chart.set_point_count(pcnt)
chart.set_ext_y_array(ser, ecg_sample)
slider = lv.slider(lv.scr_act())
slider.set_range(lv.IMG_ZOOM.NONE, lv.IMG_ZOOM.NONE * 10)
slider.add_event_cb(slider_x_event_cb, lv.EVENT.VALUE_CHANGED, None)
slider.set_size(200,10)
slider.align_to(chart, lv.ALIGN.OUT_BOTTOM_MID, 0, 20)
slider = lv.slider(lv.scr_act())
slider.set_range(lv.IMG_ZOOM.NONE, lv.IMG_ZOOM.NONE * 10)
slider.add_event_cb(slider_y_event_cb, lv.EVENT.VALUE_CHANGED, None)
slider.set_size(10, 150)
slider.align_to(chart, lv.ALIGN.OUT_RIGHT_MID, 20, 0)
Show cursor on the clicked point¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static lv_obj_t * chart;
static lv_chart_series_t * ser;
static lv_chart_cursor_t * cursor;
static void event_cb(lv_event_t * e)
{
static int32_t last_id = -1;
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
last_id = lv_chart_get_pressed_point(obj);
if(last_id != LV_CHART_POINT_NONE) {
lv_chart_set_cursor_point(obj, cursor, NULL, last_id);
}
}
else if(code == LV_EVENT_DRAW_PART_END) {
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(!lv_obj_draw_part_check_type(dsc, &lv_chart_class, LV_CHART_DRAW_PART_CURSOR)) return;
if(dsc->p1 == NULL || dsc->p2 == NULL || dsc->p1->y != dsc->p2->y || last_id < 0) return;
lv_coord_t * data_array = lv_chart_get_y_array(chart, ser);
lv_coord_t v = data_array[last_id];
char buf[16];
lv_snprintf(buf, sizeof(buf), "%d", v);
lv_point_t size;
lv_txt_get_size(&size, buf, LV_FONT_DEFAULT, 0, 0, LV_COORD_MAX, LV_TEXT_FLAG_NONE);
lv_area_t a;
a.y2 = dsc->p1->y - 5;
a.y1 = a.y2 - size.y - 10;
a.x1 = dsc->p1->x + 10;
a.x2 = a.x1 + size.x + 10;
lv_draw_rect_dsc_t draw_rect_dsc;
lv_draw_rect_dsc_init(&draw_rect_dsc);
draw_rect_dsc.bg_color = lv_palette_main(LV_PALETTE_BLUE);
draw_rect_dsc.radius = 3;
lv_draw_rect(dsc->draw_ctx, &draw_rect_dsc, &a);
lv_draw_label_dsc_t draw_label_dsc;
lv_draw_label_dsc_init(&draw_label_dsc);
draw_label_dsc.color = lv_color_white();
a.x1 += 5;
a.x2 -= 5;
a.y1 += 5;
a.y2 -= 5;
lv_draw_label(dsc->draw_ctx, &draw_label_dsc, &a, buf, NULL);
}
}
/**
* Show cursor on the clicked point
*/
void lv_example_chart_6(void)
{
chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, LV_ALIGN_CENTER, 0, -10);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_Y, 10, 5, 6, 5, true, 40);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_X, 10, 5, 10, 1, true, 30);
lv_obj_add_event_cb(chart, event_cb, LV_EVENT_ALL, NULL);
lv_obj_refresh_ext_draw_size(chart);
cursor = lv_chart_add_cursor(chart, lv_palette_main(LV_PALETTE_BLUE), LV_DIR_LEFT | LV_DIR_BOTTOM);
ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart, ser, lv_rand(10, 90));
}
lv_chart_set_zoom_x(chart, 500);
lv_obj_t * label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "Click on a point");
lv_obj_align_to(label, chart, LV_ALIGN_OUT_TOP_MID, 0, -5);
}
#endif
class ExampleChart_6():
def __init__(self):
self.last_id = -1
#
# Show cursor on the clicked point
#
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.align(lv.ALIGN.CENTER, 0, -10)
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_Y, 10, 5, 6, 5, True, 40)
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_X, 10, 5, 10, 1, True, 30)
chart.add_event_cb(self.event_cb, lv.EVENT.ALL, None)
chart.refresh_ext_draw_size()
self.cursor = chart.add_cursor(lv.palette_main(lv.PALETTE.BLUE), lv.DIR.LEFT | lv.DIR.BOTTOM)
self.ser = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
self.ser_p = []
for i in range(10):
self.ser_p.append(lv.rand(10,90))
self.ser.y_points = self.ser_p
newser = chart.get_series_next(None)
# print("length of data points: ",len(newser.points))
chart.set_zoom_x(500)
label = lv.label(lv.scr_act())
label.set_text("Click on a point")
label.align_to(chart, lv.ALIGN.OUT_TOP_MID, 0, -5)
def event_cb(self,e):
code = e.get_code()
chart = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
# print("last_id: ",self.last_id)
self.last_id = chart.get_pressed_point()
if self.last_id != lv.CHART_POINT.NONE:
p = lv.point_t()
chart.get_point_pos_by_id(self.ser, self.last_id, p)
chart.set_cursor_point(self.cursor, None, self.last_id)
elif code == lv.EVENT.DRAW_PART_END:
# print("EVENT.DRAW_PART_END")
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
# if dsc.p1 and dsc.p2:
# print("p1, p2", dsc.p1,dsc.p2)
# print("p1.y, p2.y", dsc.p1.y, dsc.p2.y)
# print("last_id: ",self.last_id)
if dsc.part == lv.PART.CURSOR and dsc.p1 and dsc.p2 and dsc.p1.y == dsc.p2.y and self.last_id >= 0:
v = self.ser_p[self.last_id]
# print("value: ",v)
value_txt = str(v)
size = lv.point_t()
lv.txt_get_size(size, value_txt, lv.font_default(), 0, 0, lv.COORD.MAX, lv.TEXT_FLAG.NONE)
a = lv.area_t()
a.y2 = dsc.p1.y - 5
a.y1 = a.y2 - size.y - 10
a.x1 = dsc.p1.x + 10
a.x2 = a.x1 + size.x + 10
draw_rect_dsc = lv.draw_rect_dsc_t()
draw_rect_dsc.init()
draw_rect_dsc.bg_color = lv.palette_main(lv.PALETTE.BLUE)
draw_rect_dsc.radius = 3
lv.draw_rect(a, dsc.clip_area, draw_rect_dsc)
draw_label_dsc = lv.draw_label_dsc_t()
draw_label_dsc.init()
draw_label_dsc.color = lv.color_white()
a.x1 += 5
a.x2 -= 5
a.y1 += 5
a.y2 -= 5
lv.draw_label(a, dsc.clip_area, draw_label_dsc, value_txt, None)
example_chart_6 = ExampleChart_6()
Scatter chart¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static void draw_event_cb(lv_event_t * e)
{
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(dsc->part == LV_PART_ITEMS) {
lv_obj_t * obj = lv_event_get_target(e);
lv_chart_series_t * ser = lv_chart_get_series_next(obj, NULL);
uint32_t cnt = lv_chart_get_point_count(obj);
/*Make older value more transparent*/
dsc->rect_dsc->bg_opa = (LV_OPA_COVER * dsc->id) / (cnt - 1);
/*Make smaller values blue, higher values red*/
lv_coord_t * x_array = lv_chart_get_x_array(obj, ser);
lv_coord_t * y_array = lv_chart_get_y_array(obj, ser);
/*dsc->id is the tells drawing order, but we need the ID of the point being drawn.*/
uint32_t start_point = lv_chart_get_x_start_point(obj, ser);
uint32_t p_act = (start_point + dsc->id) % cnt; /*Consider start point to get the index of the array*/
lv_opa_t x_opa = (x_array[p_act] * LV_OPA_50) / 200;
lv_opa_t y_opa = (y_array[p_act] * LV_OPA_50) / 1000;
dsc->rect_dsc->bg_color = lv_color_mix(lv_palette_main(LV_PALETTE_RED),
lv_palette_main(LV_PALETTE_BLUE),
x_opa + y_opa);
}
}
static void add_data(lv_timer_t * timer)
{
LV_UNUSED(timer);
lv_obj_t * chart = timer->user_data;
lv_chart_set_next_value2(chart, lv_chart_get_series_next(chart, NULL), lv_rand(0, 200), lv_rand(0, 1000));
}
/**
* A scatter chart
*/
void lv_example_chart_7(void)
{
lv_obj_t * chart = lv_chart_create(lv_scr_act());
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, LV_ALIGN_CENTER, 0, 0);
lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
lv_obj_set_style_line_width(chart, 0, LV_PART_ITEMS); /*Remove the lines*/
lv_chart_set_type(chart, LV_CHART_TYPE_SCATTER);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_X, 5, 5, 5, 1, true, 30);
lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_Y, 10, 5, 6, 5, true, 50);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_X, 0, 200);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, 0, 1000);
lv_chart_set_point_count(chart, 50);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 50; i++) {
lv_chart_set_next_value2(chart, ser, lv_rand(0, 200), lv_rand(0, 1000));
}
lv_timer_create(add_data, 100, chart);
}
#endif
#!/opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver
def draw_event_cb(e):
dsc = e.get_draw_part_dsc()
if dsc.part == lv.PART.ITEMS:
obj = e.get_target()
ser = obj.get_series_next(None)
cnt = obj.get_point_count()
# print("cnt: ",cnt)
# Make older value more transparent
dsc.rect_dsc.bg_opa = (lv.OPA.COVER * dsc.id) // (cnt - 1)
# Make smaller values blue, higher values red
# x_array = chart.get_x_array(ser)
# y_array = chart.get_y_array(ser)
# dsc->id is the tells drawing order, but we need the ID of the point being drawn.
start_point = chart.get_x_start_point(ser)
# print("start point: ",start_point)
p_act = (start_point + dsc.id) % cnt # Consider start point to get the index of the array
# print("p_act", p_act)
x_opa = (x_array[p_act] * lv.OPA._50) // 200
y_opa = (y_array[p_act] * lv.OPA._50) // 1000
dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.RED).color_mix(
lv.palette_main(lv.PALETTE.BLUE),
x_opa + y_opa)
def add_data(timer,chart):
# print("add_data")
x = lv.rand(0,200)
y = lv.rand(0,1000)
chart.set_next_value2(ser, x, y)
# chart.set_next_value2(chart.gx, y)
x_array.pop(0)
x_array.append(x)
y_array.pop(0)
y_array.append(y)
#
# A scatter chart
#
chart = lv.chart(lv.scr_act())
chart.set_size(200, 150)
chart.align(lv.ALIGN.CENTER, 0, 0)
chart.add_event_cb(draw_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
chart.set_style_line_width(0, lv.PART.ITEMS) # Remove the lines
chart.set_type(lv.chart.TYPE.SCATTER)
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_X, 5, 5, 5, 1, True, 30)
chart.set_axis_tick(lv.chart.AXIS.PRIMARY_Y, 10, 5, 6, 5, True, 50)
chart.set_range(lv.chart.AXIS.PRIMARY_X, 0, 200)
chart.set_range(lv.chart.AXIS.PRIMARY_Y, 0, 1000)
chart.set_point_count(50)
ser = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
x_array = []
y_array = []
for i in range(50):
x_array.append(lv.rand(0, 200))
y_array.append(lv.rand(0, 1000))
ser.x_points = x_array
ser.y_points = y_array
# Create an `lv_timer` to update the chart.
timer = lv.timer_create_basic()
timer.set_period(100)
timer.set_cb(lambda src: add_data(timer,chart))
Stacked area chart¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_DRAW_COMPLEX && LV_BUILD_EXAMPLES
/* A struct is used to keep track of the series list because later we need to draw to the series in the reverse order to which they were initialised. */
typedef struct {
lv_obj_t * obj;
lv_chart_series_t * series_list[3];
} stacked_area_chart_t;
static stacked_area_chart_t stacked_area_chart;
/**
* Callback which draws the blocks of colour under the lines
**/
static void draw_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
/*Add the faded area before the lines are drawn*/
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(dsc->part == LV_PART_ITEMS) {
if(!dsc->p1 || !dsc->p2)
return;
/*Add a line mask that keeps the area below the line*/
lv_draw_mask_line_param_t line_mask_param;
lv_draw_mask_line_points_init(&line_mask_param, dsc->p1->x, dsc->p1->y, dsc->p2->x, dsc->p2->y,
LV_DRAW_MASK_LINE_SIDE_BOTTOM);
int16_t line_mask_id = lv_draw_mask_add(&line_mask_param, NULL);
/*Draw a rectangle that will be affected by the mask*/
lv_draw_rect_dsc_t draw_rect_dsc;
lv_draw_rect_dsc_init(&draw_rect_dsc);
draw_rect_dsc.bg_opa = LV_OPA_COVER;
draw_rect_dsc.bg_color = dsc->line_dsc->color;
lv_area_t a;
a.x1 = dsc->p1->x;
a.x2 = dsc->p2->x;
a.y1 = LV_MIN(dsc->p1->y, dsc->p2->y);
a.y2 = obj->coords.y2 -
13; /* -13 cuts off where the rectangle draws over the chart margin. Without this an area of 0 doesn't look like 0 */
lv_draw_rect(dsc->draw_ctx, &draw_rect_dsc, &a);
/*Remove the mask*/
lv_draw_mask_free_param(&line_mask_param);
lv_draw_mask_remove_id(line_mask_id);
}
}
/**
* Helper function to round a fixed point number
**/
static int32_t round_fixed_point(int32_t n, int8_t shift)
{
/* Create a bitmask to isolates the decimal part of the fixed point number */
int32_t mask = 1;
for(int32_t bit_pos = 0; bit_pos < shift; bit_pos++) {
mask = (mask << 1) + 1;
}
int32_t decimal_part = n & mask;
/* Get 0.5 as fixed point */
int32_t rounding_boundary = 1 << (shift - 1);
/* Return either the integer part of n or the integer part + 1 */
return (decimal_part < rounding_boundary) ? (n & ~mask) : ((n >> shift) + 1) << shift;
}
/**
* Stacked area chart
*/
void lv_example_chart_8(void)
{
/*Create a stacked_area_chart.obj*/
stacked_area_chart.obj = lv_chart_create(lv_scr_act());
lv_obj_set_size(stacked_area_chart.obj, 200, 150);
lv_obj_center(stacked_area_chart.obj);
lv_chart_set_type(stacked_area_chart.obj, LV_CHART_TYPE_LINE);
lv_chart_set_div_line_count(stacked_area_chart.obj, 5, 7);
lv_obj_add_event_cb(stacked_area_chart.obj, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
/* Set range to 0 to 100 for percentages. Draw ticks */
lv_chart_set_range(stacked_area_chart.obj, LV_CHART_AXIS_PRIMARY_Y, 0, 100);
lv_chart_set_axis_tick(stacked_area_chart.obj, LV_CHART_AXIS_PRIMARY_Y, 3, 0, 5, 1, true, 30);
/*Set point size to 0 so the lines are smooth */
lv_obj_set_style_size(stacked_area_chart.obj, 0, LV_PART_INDICATOR);
/*Add some data series*/
stacked_area_chart.series_list[0] = lv_chart_add_series(stacked_area_chart.obj, lv_palette_main(LV_PALETTE_RED),
LV_CHART_AXIS_PRIMARY_Y);
stacked_area_chart.series_list[1] = lv_chart_add_series(stacked_area_chart.obj, lv_palette_main(LV_PALETTE_BLUE),
LV_CHART_AXIS_PRIMARY_Y);
stacked_area_chart.series_list[2] = lv_chart_add_series(stacked_area_chart.obj, lv_palette_main(LV_PALETTE_GREEN),
LV_CHART_AXIS_PRIMARY_Y);
for(int point = 0; point < 10; point++) {
/* Make some random data */
uint32_t vals[3] = {lv_rand(10, 20), lv_rand(20, 30), lv_rand(20, 30)};
int8_t fixed_point_shift = 5;
uint32_t total = vals[0] + vals[1] + vals[2];
uint32_t draw_heights[3];
uint32_t int_sum = 0;
uint32_t decimal_sum = 0;
/* Fixed point cascade rounding ensures percentages add to 100 */
for(int32_t series_index = 0; series_index < 3; series_index++) {
decimal_sum += (((vals[series_index] * 100) << fixed_point_shift) / total);
int_sum += (vals[series_index] * 100) / total;
int32_t modifier = (round_fixed_point(decimal_sum, fixed_point_shift) >> fixed_point_shift) - int_sum;
/* The draw heights are equal to the percentage of the total each value is + the cumulative sum of the previous percentages.
The accumulation is how the values get "stacked" */
draw_heights[series_index] = int_sum + modifier;
/* Draw to the series in the reverse order to which they were initialised.
Without this the higher values will draw on top of the lower ones.
This is because the Z-height of a series matches the order it was initialised */
lv_chart_set_next_value(stacked_area_chart.obj, stacked_area_chart.series_list[3 - series_index - 1],
draw_heights[series_index]);
}
}
lv_chart_refresh(stacked_area_chart.obj);
}
#endif
import display_driver
import lvgl as lv
# A class is used to keep track of the series list because later we
# need to draw to the series in the reverse order to which they were initialised.
class StackedAreaChart:
def __init__(self):
self.obj = None
self.series_list = [None, None, None]
stacked_area_chart = StackedAreaChart()
#
# Callback which draws the blocks of colour under the lines
#
def draw_event_cb(e):
obj = e.get_target()
cont_a = lv.area_t()
obj.get_coords(cont_a)
#Add the faded area before the lines are drawn
dsc = e.get_draw_part_dsc()
if dsc.part == lv.PART.ITEMS:
if not dsc.p1 or not dsc.p2:
return
# Add a line mask that keeps the area below the line
line_mask_param = lv.draw_mask_line_param_t()
line_mask_param.points_init(dsc.p1.x, dsc.p1.y, dsc.p2.x, dsc.p2.y, lv.DRAW_MASK_LINE_SIDE.BOTTOM)
line_mask_id = lv.draw_mask_add(line_mask_param, None)
#Draw a rectangle that will be affected by the mask
draw_rect_dsc = lv.draw_rect_dsc_t()
draw_rect_dsc.init()
draw_rect_dsc.bg_opa = lv.OPA.COVER
draw_rect_dsc.bg_color = dsc.line_dsc.color
a = lv.area_t()
a.x1 = dsc.p1.x
a.x2 = dsc.p2.x
a.y1 = min(dsc.p1.y, dsc.p2.y)
a.y2 = cont_a.y2 - 13 # -13 cuts off where the rectangle draws over the chart margin. Without this an area of 0 doesn't look like 0
dsc.draw_ctx.rect(draw_rect_dsc, a)
# Remove the mask
lv.draw_mask_free_param(line_mask_param)
lv.draw_mask_remove_id(line_mask_id)
#
# Helper function to round a fixed point number
#
def round_fixed_point(n, shift):
# Create a bitmask to isolates the decimal part of the fixed point number
mask = 1
for bit_pos in range(shift):
mask = (mask << 1) + 1
decimal_part = n & mask
# Get 0.5 as fixed point
rounding_boundary = 1 << (shift - 1)
# Return either the integer part of n or the integer part + 1
if decimal_part < rounding_boundary:
return (n & ~mask)
return ((n >> shift) + 1) << shift
#
# Stacked area chart
#
def lv_example_chart_8():
#Create a stacked_area_chart.obj
stacked_area_chart.obj = lv.chart(lv.scr_act())
stacked_area_chart.obj.set_size(200, 150)
stacked_area_chart.obj.center()
stacked_area_chart.obj.set_type( lv.chart.TYPE.LINE)
stacked_area_chart.obj.set_div_line_count(5, 7)
stacked_area_chart.obj.add_event_cb( draw_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
# Set range to 0 to 100 for percentages. Draw ticks
stacked_area_chart.obj.set_range(lv.chart.AXIS.PRIMARY_Y,0,100)
stacked_area_chart.obj.set_axis_tick(lv.chart.AXIS.PRIMARY_Y, 3, 0, 5, 1, True, 30)
#Set point size to 0 so the lines are smooth
stacked_area_chart.obj.set_style_size(0, lv.PART.INDICATOR)
# Add some data series
stacked_area_chart.series_list[0] = stacked_area_chart.obj.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
stacked_area_chart.series_list[1] = stacked_area_chart.obj.add_series(lv.palette_main(lv.PALETTE.BLUE), lv.chart.AXIS.PRIMARY_Y)
stacked_area_chart.series_list[2] = stacked_area_chart.obj.add_series(lv.palette_main(lv.PALETTE.GREEN), lv.chart.AXIS.PRIMARY_Y)
for point in range(10):
# Make some random data
vals = [lv.rand(10, 20), lv.rand(20, 30), lv.rand(20, 30)]
fixed_point_shift = 5
total = vals[0] + vals[1] + vals[2]
draw_heights = [0, 0, 0]
int_sum = 0
decimal_sum = 0
# Fixed point cascade rounding ensures percentages add to 100
for series_index in range(3):
decimal_sum += int(((vals[series_index] * 100) << fixed_point_shift) // total)
int_sum += int((vals[series_index] * 100) / total)
modifier = (round_fixed_point(decimal_sum, fixed_point_shift) >> fixed_point_shift) - int_sum
# The draw heights are equal to the percentage of the total each value is + the cumulative sum of the previous percentages.
# The accumulation is how the values get "stacked"
draw_heights[series_index] = int(int_sum + modifier)
# Draw to the series in the reverse order to which they were initialised.
# Without this the higher values will draw on top of the lower ones.
# This is because the Z-height of a series matches the order it was initialised
stacked_area_chart.obj.set_next_value( stacked_area_chart.series_list[3 - series_index - 1], draw_heights[series_index])
stacked_area_chart.obj.refresh()
lv_example_chart_8()
Checkbox¶
Simple Checkboxes¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHECKBOX && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
const char * txt = lv_checkbox_get_text(obj);
const char * state = lv_obj_get_state(obj) & LV_STATE_CHECKED ? "Checked" : "Unchecked";
LV_LOG_USER("%s: %s", txt, state);
}
}
void lv_example_checkbox_1(void)
{
lv_obj_set_flex_flow(lv_scr_act(), LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(lv_scr_act(), LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_CENTER);
lv_obj_t * cb;
cb = lv_checkbox_create(lv_scr_act());
lv_checkbox_set_text(cb, "Apple");
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_scr_act());
lv_checkbox_set_text(cb, "Banana");
lv_obj_add_state(cb, LV_STATE_CHECKED);
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_scr_act());
lv_checkbox_set_text(cb, "Lemon");
lv_obj_add_state(cb, LV_STATE_DISABLED);
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_scr_act());
lv_obj_add_state(cb, LV_STATE_CHECKED | LV_STATE_DISABLED);
lv_checkbox_set_text(cb, "Melon\nand a new line");
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
lv_obj_update_layout(cb);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
txt = obj.get_text()
if obj.get_state() & lv.STATE.CHECKED:
state = "Checked"
else:
state = "Unchecked"
print(txt + ":" + state)
lv.scr_act().set_flex_flow(lv.FLEX_FLOW.COLUMN)
lv.scr_act().set_flex_align(lv.FLEX_ALIGN.CENTER, lv.FLEX_ALIGN.START, lv.FLEX_ALIGN.CENTER)
cb = lv.checkbox(lv.scr_act())
cb.set_text("Apple")
cb.add_event_cb(event_handler, lv.EVENT.ALL, None)
cb = lv.checkbox(lv.scr_act())
cb.set_text("Banana")
cb.add_state(lv.STATE.CHECKED)
cb.add_event_cb(event_handler, lv.EVENT.ALL, None)
cb = lv.checkbox(lv.scr_act())
cb.set_text("Lemon")
cb.add_state(lv.STATE.DISABLED)
cb.add_event_cb(event_handler, lv.EVENT.ALL, None)
cb = lv.checkbox(lv.scr_act())
cb.add_state(lv.STATE.CHECKED | lv.STATE.DISABLED)
cb.set_text("Melon")
cb.add_event_cb(event_handler, lv.EVENT.ALL, None)
cb.update_layout()
Checkboxes as radio buttons¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_CHECKBOX && LV_BUILD_EXAMPLES
static lv_style_t style_radio;
static lv_style_t style_radio_chk;
static uint32_t active_index_1 = 0;
static uint32_t active_index_2 = 0;
static void radio_event_handler(lv_event_t * e)
{
uint32_t * active_id = lv_event_get_user_data(e);
lv_obj_t * cont = lv_event_get_current_target(e);
lv_obj_t * act_cb = lv_event_get_target(e);
lv_obj_t * old_cb = lv_obj_get_child(cont, *active_id);
/*Do nothing if the container was clicked*/
if(act_cb == cont) return;
lv_obj_clear_state(old_cb, LV_STATE_CHECKED); /*Uncheck the previous radio button*/
lv_obj_add_state(act_cb, LV_STATE_CHECKED); /*Uncheck the current radio button*/
*active_id = lv_obj_get_index(act_cb);
LV_LOG_USER("Selected radio buttons: %d, %d", (int)active_index_1, (int)active_index_2);
}
static void radiobutton_create(lv_obj_t * parent, const char * txt)
{
lv_obj_t * obj = lv_checkbox_create(parent);
lv_checkbox_set_text(obj, txt);
lv_obj_add_flag(obj, LV_OBJ_FLAG_EVENT_BUBBLE);
lv_obj_add_style(obj, &style_radio, LV_PART_INDICATOR);
lv_obj_add_style(obj, &style_radio_chk, LV_PART_INDICATOR | LV_STATE_CHECKED);
}
/**
* Checkboxes as radio buttons
*/
void lv_example_checkbox_2(void)
{
/* The idea is to enable `LV_OBJ_FLAG_EVENT_BUBBLE` on checkboxes and process the
* `LV_EVENT_CLICKED` on the container.
* A variable is passed as event user data where the index of the active
* radiobutton is saved */
lv_style_init(&style_radio);
lv_style_set_radius(&style_radio, LV_RADIUS_CIRCLE);
lv_style_init(&style_radio_chk);
lv_style_set_bg_img_src(&style_radio_chk, NULL);
uint32_t i;
char buf[32];
lv_obj_t * cont1 = lv_obj_create(lv_scr_act());
lv_obj_set_flex_flow(cont1, LV_FLEX_FLOW_COLUMN);
lv_obj_set_size(cont1, lv_pct(40), lv_pct(80));
lv_obj_add_event_cb(cont1, radio_event_handler, LV_EVENT_CLICKED, &active_index_1);
for(i = 0; i < 5; i++) {
lv_snprintf(buf, sizeof(buf), "A %d", (int)i + 1);
radiobutton_create(cont1, buf);
}
/*Make the first checkbox checked*/
lv_obj_add_state(lv_obj_get_child(cont1, 0), LV_STATE_CHECKED);
lv_obj_t * cont2 = lv_obj_create(lv_scr_act());
lv_obj_set_flex_flow(cont2, LV_FLEX_FLOW_COLUMN);
lv_obj_set_size(cont2, lv_pct(40), lv_pct(80));
lv_obj_set_x(cont2, lv_pct(50));
lv_obj_add_event_cb(cont2, radio_event_handler, LV_EVENT_CLICKED, &active_index_2);
for(i = 0; i < 3; i++) {
lv_snprintf(buf, sizeof(buf), "B %d", (int)i + 1);
radiobutton_create(cont2, buf);
}
/*Make the first checkbox checked*/
lv_obj_add_state(lv_obj_get_child(cont2, 0), LV_STATE_CHECKED);
}
#endif
Error encountered while trying to open /home/runner/work/lvgl/lvgl/examples/widgets/checkbox/lv_example_checkbox_2.py
Colorwheel¶
Simple Colorwheel¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_COLORWHEEL && LV_BUILD_EXAMPLES
void lv_example_colorwheel_1(void)
{
lv_obj_t * cw;
cw = lv_colorwheel_create(lv_scr_act(), true);
lv_obj_set_size(cw, 200, 200);
lv_obj_center(cw);
}
#endif
cw = lv.colorwheel(lv.scr_act(), True)
cw.set_size(200, 200)
cw.center()
Dropdown¶
Simple Drop down list¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_DROPDOWN && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_dropdown_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Option: %s", buf);
}
}
void lv_example_dropdown_1(void)
{
/*Create a normal drop down list*/
lv_obj_t * dd = lv_dropdown_create(lv_scr_act());
lv_dropdown_set_options(dd, "Apple\n"
"Banana\n"
"Orange\n"
"Cherry\n"
"Grape\n"
"Raspberry\n"
"Melon\n"
"Orange\n"
"Lemon\n"
"Nuts");
lv_obj_align(dd, LV_ALIGN_TOP_MID, 0, 20);
lv_obj_add_event_cb(dd, event_handler, LV_EVENT_ALL, NULL);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
option = " "*10 # should be large enough to store the option
obj.get_selected_str(option, len(option))
# .strip() removes trailing spaces
print("Option: \"%s\"" % option.strip())
# Create a normal drop down list
dd = lv.dropdown(lv.scr_act())
dd.set_options("\n".join([
"Apple",
"Banana",
"Orange",
"Cherry",
"Grape",
"Raspberry",
"Melon",
"Orange",
"Lemon",
"Nuts"]))
dd.align(lv.ALIGN.TOP_MID, 0, 20)
dd.add_event_cb(event_handler, lv.EVENT.ALL, None)
Drop down in four directions¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_DROPDOWN && LV_BUILD_EXAMPLES
/**
* Create a drop down, up, left and right menus
*/
void lv_example_dropdown_2(void)
{
static const char * opts = "Apple\n"
"Banana\n"
"Orange\n"
"Melon";
lv_obj_t * dd;
dd = lv_dropdown_create(lv_scr_act());
lv_dropdown_set_options_static(dd, opts);
lv_obj_align(dd, LV_ALIGN_TOP_MID, 0, 10);
dd = lv_dropdown_create(lv_scr_act());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_BOTTOM);
lv_dropdown_set_symbol(dd, LV_SYMBOL_UP);
lv_obj_align(dd, LV_ALIGN_BOTTOM_MID, 0, -10);
dd = lv_dropdown_create(lv_scr_act());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_RIGHT);
lv_dropdown_set_symbol(dd, LV_SYMBOL_RIGHT);
lv_obj_align(dd, LV_ALIGN_LEFT_MID, 10, 0);
dd = lv_dropdown_create(lv_scr_act());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_LEFT);
lv_dropdown_set_symbol(dd, LV_SYMBOL_LEFT);
lv_obj_align(dd, LV_ALIGN_RIGHT_MID, -10, 0);
}
#endif
#
# Create a drop down, up, left and right menus
#
opts = "\n".join([
"Apple",
"Banana",
"Orange",
"Melon",
"Grape",
"Raspberry"])
dd = lv.dropdown(lv.scr_act())
dd.set_options_static(opts)
dd.align(lv.ALIGN.TOP_MID, 0, 10)
dd = lv.dropdown(lv.scr_act())
dd.set_options_static(opts)
dd.set_dir(lv.DIR.BOTTOM)
dd.set_symbol(lv.SYMBOL.UP)
dd.align(lv.ALIGN.BOTTOM_MID, 0, -10)
dd = lv.dropdown(lv.scr_act())
dd.set_options_static(opts)
dd.set_dir(lv.DIR.RIGHT)
dd.set_symbol(lv.SYMBOL.RIGHT)
dd.align(lv.ALIGN.LEFT_MID, 10, 0)
dd = lv.dropdown(lv.scr_act())
dd.set_options_static(opts)
dd.set_dir(lv.DIR.LEFT)
dd.set_symbol(lv.SYMBOL.LEFT)
dd.align(lv.ALIGN.RIGHT_MID, -10, 0)
Image¶
Image from variable and symbol¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_IMG && LV_BUILD_EXAMPLES
void lv_example_img_1(void)
{
LV_IMG_DECLARE(img_cogwheel_argb);
lv_obj_t * img1 = lv_img_create(lv_scr_act());
lv_img_set_src(img1, &img_cogwheel_argb);
lv_obj_align(img1, LV_ALIGN_CENTER, 0, -20);
lv_obj_set_size(img1, 200, 200);
lv_obj_t * img2 = lv_img_create(lv_scr_act());
lv_img_set_src(img2, LV_SYMBOL_OK "Accept");
lv_obj_align_to(img2, img1, LV_ALIGN_OUT_BOTTOM_MID, 0, 20);
}
#endif
#!/opt/bin/lv_micropython -i
import usys as sys
import lvgl as lv
import display_driver
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_cogwheel_argb.png','rb') as f:
png_data = f.read()
except:
print("Could not find img_cogwheel_argb.png")
sys.exit()
img_cogwheel_argb = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
img1 = lv.img(lv.scr_act())
img1.set_src(img_cogwheel_argb)
img1.align(lv.ALIGN.CENTER, 0, -20)
img1.set_size(200, 200)
img2 = lv.img(lv.scr_act())
img2.set_src(lv.SYMBOL.OK + "Accept")
img2.align_to(img1, lv.ALIGN.OUT_BOTTOM_MID, 0, 20)
Image recoloring¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_IMG && LV_USE_SLIDER && LV_BUILD_EXAMPLES
static lv_obj_t * create_slider(lv_color_t color);
static void slider_event_cb(lv_event_t * e);
static lv_obj_t * red_slider, * green_slider, * blue_slider, * intense_slider;
static lv_obj_t * img1;
/**
* Demonstrate runtime image re-coloring
*/
void lv_example_img_2(void)
{
/*Create 4 sliders to adjust RGB color and re-color intensity*/
red_slider = create_slider(lv_palette_main(LV_PALETTE_RED));
green_slider = create_slider(lv_palette_main(LV_PALETTE_GREEN));
blue_slider = create_slider(lv_palette_main(LV_PALETTE_BLUE));
intense_slider = create_slider(lv_palette_main(LV_PALETTE_GREY));
lv_slider_set_value(red_slider, LV_OPA_20, LV_ANIM_OFF);
lv_slider_set_value(green_slider, LV_OPA_90, LV_ANIM_OFF);
lv_slider_set_value(blue_slider, LV_OPA_60, LV_ANIM_OFF);
lv_slider_set_value(intense_slider, LV_OPA_50, LV_ANIM_OFF);
lv_obj_align(red_slider, LV_ALIGN_LEFT_MID, 25, 0);
lv_obj_align_to(green_slider, red_slider, LV_ALIGN_OUT_RIGHT_MID, 25, 0);
lv_obj_align_to(blue_slider, green_slider, LV_ALIGN_OUT_RIGHT_MID, 25, 0);
lv_obj_align_to(intense_slider, blue_slider, LV_ALIGN_OUT_RIGHT_MID, 25, 0);
/*Now create the actual image*/
LV_IMG_DECLARE(img_cogwheel_argb)
img1 = lv_img_create(lv_scr_act());
lv_img_set_src(img1, &img_cogwheel_argb);
lv_obj_align(img1, LV_ALIGN_RIGHT_MID, -20, 0);
lv_event_send(intense_slider, LV_EVENT_VALUE_CHANGED, NULL);
}
static void slider_event_cb(lv_event_t * e)
{
LV_UNUSED(e);
/*Recolor the image based on the sliders' values*/
lv_color_t color = lv_color_make(lv_slider_get_value(red_slider), lv_slider_get_value(green_slider),
lv_slider_get_value(blue_slider));
lv_opa_t intense = lv_slider_get_value(intense_slider);
lv_obj_set_style_img_recolor_opa(img1, intense, 0);
lv_obj_set_style_img_recolor(img1, color, 0);
}
static lv_obj_t * create_slider(lv_color_t color)
{
lv_obj_t * slider = lv_slider_create(lv_scr_act());
lv_slider_set_range(slider, 0, 255);
lv_obj_set_size(slider, 10, 200);
lv_obj_set_style_bg_color(slider, color, LV_PART_KNOB);
lv_obj_set_style_bg_color(slider, lv_color_darken(color, LV_OPA_40), LV_PART_INDICATOR);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
return slider;
}
#endif
#!/opt/bin/lv_micropython -i
import usys as sys
import lvgl as lv
import display_driver
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_cogwheel_argb.png','rb') as f:
png_data = f.read()
except:
print("Could not find img_cogwheel_argb.png")
sys.exit()
img_cogwheel_argb = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
def create_slider(color):
slider = lv.slider(lv.scr_act())
slider.set_range(0, 255)
slider.set_size(10, 200)
slider.set_style_bg_color(color, lv.PART.KNOB)
slider.set_style_bg_color(color.color_darken(lv.OPA._40), lv.PART.INDICATOR)
slider.add_event_cb(slider_event_cb, lv.EVENT.VALUE_CHANGED, None)
return slider
def slider_event_cb(e):
# Recolor the image based on the sliders' values
color = lv.color_make(red_slider.get_value(), green_slider.get_value(), blue_slider.get_value())
intense = intense_slider.get_value()
img1.set_style_img_recolor_opa(intense, 0)
img1.set_style_img_recolor(color, 0)
#
# Demonstrate runtime image re-coloring
#
# Create 4 sliders to adjust RGB color and re-color intensity
red_slider = create_slider(lv.palette_main(lv.PALETTE.RED))
green_slider = create_slider(lv.palette_main(lv.PALETTE.GREEN))
blue_slider = create_slider(lv.palette_main(lv.PALETTE.BLUE))
intense_slider = create_slider(lv.palette_main(lv.PALETTE.GREY))
red_slider.set_value(lv.OPA._20, lv.ANIM.OFF)
green_slider.set_value(lv.OPA._90, lv.ANIM.OFF)
blue_slider.set_value(lv.OPA._60, lv.ANIM.OFF)
intense_slider.set_value(lv.OPA._50, lv.ANIM.OFF)
red_slider.align(lv.ALIGN.LEFT_MID, 25, 0)
green_slider.align_to(red_slider, lv.ALIGN.OUT_RIGHT_MID, 25, 0)
blue_slider.align_to(green_slider, lv.ALIGN.OUT_RIGHT_MID, 25, 0)
intense_slider.align_to(blue_slider, lv.ALIGN.OUT_RIGHT_MID, 25, 0)
# Now create the actual image
img1 = lv.img(lv.scr_act())
img1.set_src(img_cogwheel_argb)
img1.align(lv.ALIGN.RIGHT_MID, -20, 0)
lv.event_send(intense_slider, lv.EVENT.VALUE_CHANGED, None)
Rotate and zoom¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_IMG && LV_BUILD_EXAMPLES
static void set_angle(void * img, int32_t v)
{
lv_img_set_angle(img, v);
}
static void set_zoom(void * img, int32_t v)
{
lv_img_set_zoom(img, v);
}
/**
* Show transformations (zoom and rotation) using a pivot point.
*/
void lv_example_img_3(void)
{
LV_IMG_DECLARE(img_cogwheel_argb);
/*Now create the actual image*/
lv_obj_t * img = lv_img_create(lv_scr_act());
lv_img_set_src(img, &img_cogwheel_argb);
lv_obj_align(img, LV_ALIGN_CENTER, 50, 50);
lv_img_set_pivot(img, 0, 0); /*Rotate around the top left corner*/
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, img);
lv_anim_set_exec_cb(&a, set_angle);
lv_anim_set_values(&a, 0, 3600);
lv_anim_set_time(&a, 5000);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, set_zoom);
lv_anim_set_values(&a, 128, 256);
lv_anim_set_playback_time(&a, 3000);
lv_anim_start(&a);
}
#endif
#!/opt/bin/lv_micropython -i
import usys as sys
import lvgl as lv
import display_driver
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_cogwheel_argb.png','rb') as f:
png_data = f.read()
except:
print("Could not find img_cogwheel_argb.png")
sys.exit()
img_cogwheel_argb = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
def set_angle(img, v):
img.set_angle(v)
def set_zoom(img, v):
img.set_zoom(v)
#
# Show transformations (zoom and rotation) using a pivot point.
#
# Now create the actual image
img = lv.img(lv.scr_act())
img.set_src(img_cogwheel_argb)
img.align(lv.ALIGN.CENTER, 50, 50)
img.set_pivot(0, 0) # Rotate around the top left corner
a1 = lv.anim_t()
a1.init()
a1.set_var(img)
a1.set_custom_exec_cb(lambda a,val: set_angle(img,val))
a1.set_values(0, 3600)
a1.set_time(5000)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
lv.anim_t.start(a1)
a2 = lv.anim_t()
a2.init()
a2.set_var(img)
a2.set_custom_exec_cb(lambda a,val: set_zoom(img,val))
a2.set_values(128, 256)
a2.set_time(5000)
a2.set_playback_time(3000)
a2.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
lv.anim_t.start(a2)
Image offset and styling¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_IMG && LV_BUILD_EXAMPLES
static void ofs_y_anim(void * img, int32_t v)
{
lv_img_set_offset_y(img, v);
}
/**
* Image styling and offset
*/
void lv_example_img_4(void)
{
LV_IMG_DECLARE(img_skew_strip);
static lv_style_t style;
lv_style_init(&style);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_YELLOW));
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_img_recolor_opa(&style, LV_OPA_COVER);
lv_style_set_img_recolor(&style, lv_color_black());
lv_obj_t * img = lv_img_create(lv_scr_act());
lv_obj_add_style(img, &style, 0);
lv_img_set_src(img, &img_skew_strip);
lv_obj_set_size(img, 150, 100);
lv_obj_center(img);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, img);
lv_anim_set_exec_cb(&a, ofs_y_anim);
lv_anim_set_values(&a, 0, 100);
lv_anim_set_time(&a, 3000);
lv_anim_set_playback_time(&a, 500);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
from imagetools import get_png_info, open_png
def ofs_y_anim(img, v):
img.set_offset_y(v)
# print(img,v)
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_skew_strip.png','rb') as f:
png_data = f.read()
except:
print("Could not find img_skew_strip.png")
sys.exit()
img_skew_strip = lv.img_dsc_t({
'data_size': len(png_data),
'data': png_data
})
#
# Image styling and offset
#
style = lv.style_t()
style.init()
style.set_bg_color(lv.palette_main(lv.PALETTE.YELLOW))
style.set_bg_opa(lv.OPA.COVER)
style.set_img_recolor_opa(lv.OPA.COVER)
style.set_img_recolor(lv.color_black())
img = lv.img(lv.scr_act())
img.add_style(style, 0)
img.set_src(img_skew_strip)
img.set_size(150, 100)
img.center()
a = lv.anim_t()
a.init()
a.set_var(img)
a.set_values(0, 100)
a.set_time(3000)
a.set_playback_time(500)
a.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a.set_custom_exec_cb(lambda a,val: ofs_y_anim(img,val))
lv.anim_t.start(a)
Image button¶
Simple Image button¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_IMGBTN && LV_BUILD_EXAMPLES
void lv_example_imgbtn_1(void)
{
LV_IMG_DECLARE(imgbtn_left);
LV_IMG_DECLARE(imgbtn_right);
LV_IMG_DECLARE(imgbtn_mid);
/*Create a transition animation on width transformation and recolor.*/
static lv_style_prop_t tr_prop[] = {LV_STYLE_TRANSFORM_WIDTH, LV_STYLE_IMG_RECOLOR_OPA, 0};
static lv_style_transition_dsc_t tr;
lv_style_transition_dsc_init(&tr, tr_prop, lv_anim_path_linear, 200, 0, NULL);
static lv_style_t style_def;
lv_style_init(&style_def);
lv_style_set_text_color(&style_def, lv_color_white());
lv_style_set_transition(&style_def, &tr);
/*Darken the button when pressed and make it wider*/
static lv_style_t style_pr;
lv_style_init(&style_pr);
lv_style_set_img_recolor_opa(&style_pr, LV_OPA_30);
lv_style_set_img_recolor(&style_pr, lv_color_black());
lv_style_set_transform_width(&style_pr, 20);
/*Create an image button*/
lv_obj_t * imgbtn1 = lv_imgbtn_create(lv_scr_act());
lv_imgbtn_set_src(imgbtn1, LV_IMGBTN_STATE_RELEASED, &imgbtn_left, &imgbtn_mid, &imgbtn_right);
lv_obj_add_style(imgbtn1, &style_def, 0);
lv_obj_add_style(imgbtn1, &style_pr, LV_STATE_PRESSED);
lv_obj_align(imgbtn1, LV_ALIGN_CENTER, 0, 0);
/*Create a label on the image button*/
lv_obj_t * label = lv_label_create(imgbtn1);
lv_label_set_text(label, "Button");
lv_obj_align(label, LV_ALIGN_CENTER, 0, -4);
}
#endif
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/imgbtn_left.png','rb') as f:
imgbtn_left_data = f.read()
except:
print("Could not find imgbtn_left.png")
sys.exit()
imgbtn_left_dsc = lv.img_dsc_t({
'data_size': len(imgbtn_left_data),
'data': imgbtn_left_data
})
try:
with open('../../assets/imgbtn_mid.png','rb') as f:
imgbtn_mid_data = f.read()
except:
print("Could not find imgbtn_mid.png")
sys.exit()
imgbtn_mid_dsc = lv.img_dsc_t({
'data_size': len(imgbtn_mid_data),
'data': imgbtn_mid_data
})
try:
with open('../../assets/imgbtn_right.png','rb') as f:
imgbtn_right_data = f.read()
except:
print("Could not find imgbtn_right.png")
sys.exit()
imgbtn_right_dsc = lv.img_dsc_t({
'data_size': len(imgbtn_right_data),
'data': imgbtn_right_data
})
# Create a transition animation on width transformation and recolor.
tr_prop = [lv.STYLE.TRANSFORM_WIDTH, lv.STYLE.IMG_RECOLOR_OPA, 0]
tr = lv.style_transition_dsc_t()
tr.init(tr_prop, lv.anim_t.path_linear, 200, 0, None)
style_def = lv.style_t()
style_def.init()
style_def.set_text_color(lv.color_white())
style_def.set_transition(tr)
# Darken the button when pressed and make it wider
style_pr = lv.style_t()
style_pr.init()
style_pr.set_img_recolor_opa(lv.OPA._30)
style_pr.set_img_recolor(lv.color_black())
style_pr.set_transform_width(20)
# Create an image button
imgbtn1 = lv.imgbtn(lv.scr_act())
imgbtn1.set_src(lv.imgbtn.STATE.RELEASED, imgbtn_left_dsc, imgbtn_mid_dsc, imgbtn_right_dsc)
imgbtn1.add_style(style_def, 0)
imgbtn1.add_style(style_pr, lv.STATE.PRESSED)
imgbtn1.align(lv.ALIGN.CENTER, 0, 0)
# Create a label on the image button
label = lv.label(imgbtn1)
label.set_text("Button")
label.align(lv.ALIGN.CENTER, 0, -4)
Keyboard¶
Keyboard with text area¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * ta = lv_event_get_target(e);
lv_obj_t * kb = lv_event_get_user_data(e);
if(code == LV_EVENT_FOCUSED) {
lv_keyboard_set_textarea(kb, ta);
lv_obj_clear_flag(kb, LV_OBJ_FLAG_HIDDEN);
}
if(code == LV_EVENT_DEFOCUSED) {
lv_keyboard_set_textarea(kb, NULL);
lv_obj_add_flag(kb, LV_OBJ_FLAG_HIDDEN);
}
}
void lv_example_keyboard_1(void)
{
/*Create a keyboard to use it with an of the text areas*/
lv_obj_t * kb = lv_keyboard_create(lv_scr_act());
/*Create a text area. The keyboard will write here*/
lv_obj_t * ta;
ta = lv_textarea_create(lv_scr_act());
lv_obj_align(ta, LV_ALIGN_TOP_LEFT, 10, 10);
lv_obj_add_event_cb(ta, ta_event_cb, LV_EVENT_ALL, kb);
lv_textarea_set_placeholder_text(ta, "Hello");
lv_obj_set_size(ta, 140, 80);
ta = lv_textarea_create(lv_scr_act());
lv_obj_align(ta, LV_ALIGN_TOP_RIGHT, -10, 10);
lv_obj_add_event_cb(ta, ta_event_cb, LV_EVENT_ALL, kb);
lv_obj_set_size(ta, 140, 80);
lv_keyboard_set_textarea(kb, ta);
}
#endif
def ta_event_cb(e,kb):
code = e.get_code()
ta = e.get_target()
if code == lv.EVENT.FOCUSED:
kb.set_textarea(ta)
kb.clear_flag(lv.obj.FLAG.HIDDEN)
if code == lv.EVENT.DEFOCUSED:
kb.set_textarea(None)
kb.add_flag(lv.obj.FLAG.HIDDEN)
# Create a keyboard to use it with one of the text areas
kb = lv.keyboard(lv.scr_act())
# Create a text area. The keyboard will write here
ta = lv.textarea(lv.scr_act())
ta.set_width(200)
ta.align(lv.ALIGN.TOP_LEFT, 10, 10)
ta.add_event_cb(lambda e: ta_event_cb(e,kb), lv.EVENT.ALL, None)
ta.set_placeholder_text("Hello")
ta = lv.textarea(lv.scr_act())
ta.set_width(200)
ta.align(lv.ALIGN.TOP_RIGHT, -10, 10)
ta.add_event_cb(lambda e: ta_event_cb(e,kb), lv.EVENT.ALL, None)
kb.set_textarea(ta)
Label¶
Line wrap, recoloring and scrolling¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Show line wrap, re-color, line align and text scrolling.
*/
void lv_example_label_1(void)
{
lv_obj_t * label1 = lv_label_create(lv_scr_act());
lv_label_set_long_mode(label1, LV_LABEL_LONG_WRAP); /*Break the long lines*/
lv_label_set_recolor(label1, true); /*Enable re-coloring by commands in the text*/
lv_label_set_text(label1, "#0000ff Re-color# #ff00ff words# #ff0000 of a# label, align the lines to the center "
"and wrap long text automatically.");
lv_obj_set_width(label1, 150); /*Set smaller width to make the lines wrap*/
lv_obj_set_style_text_align(label1, LV_TEXT_ALIGN_CENTER, 0);
lv_obj_align(label1, LV_ALIGN_CENTER, 0, -40);
lv_obj_t * label2 = lv_label_create(lv_scr_act());
lv_label_set_long_mode(label2, LV_LABEL_LONG_SCROLL_CIRCULAR); /*Circular scroll*/
lv_obj_set_width(label2, 150);
lv_label_set_text(label2, "It is a circularly scrolling text. ");
lv_obj_align(label2, LV_ALIGN_CENTER, 0, 40);
}
#endif
#
# Show line wrap, re-color, line align and text scrolling.
#
label1 = lv.label(lv.scr_act())
label1.set_long_mode(lv.label.LONG.WRAP) # Break the long lines*/
label1.set_recolor(True) # Enable re-coloring by commands in the text
label1.set_text("#0000ff Re-color# #ff00ff words# #ff0000 of a# label, align the lines to the center"
"and wrap long text automatically.")
label1.set_width(150) # Set smaller width to make the lines wrap
label1.set_style_text_align(lv.ALIGN.CENTER, 0)
label1.align(lv.ALIGN.CENTER, 0, -40)
label2 = lv.label(lv.scr_act())
label2.set_long_mode(lv.label.LONG.SCROLL_CIRCULAR) # Circular scroll
label2.set_width(150)
label2.set_text("It is a circularly scrolling text. ")
label2.align(lv.ALIGN.CENTER, 0, 40)
Text shadow¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Create a fake text shadow
*/
void lv_example_label_2(void)
{
/*Create a style for the shadow*/
static lv_style_t style_shadow;
lv_style_init(&style_shadow);
lv_style_set_text_opa(&style_shadow, LV_OPA_30);
lv_style_set_text_color(&style_shadow, lv_color_black());
/*Create a label for the shadow first (it's in the background)*/
lv_obj_t * shadow_label = lv_label_create(lv_scr_act());
lv_obj_add_style(shadow_label, &style_shadow, 0);
/*Create the main label*/
lv_obj_t * main_label = lv_label_create(lv_scr_act());
lv_label_set_text(main_label, "A simple method to create\n"
"shadows on a text.\n"
"It even works with\n\n"
"newlines and spaces.");
/*Set the same text for the shadow label*/
lv_label_set_text(shadow_label, lv_label_get_text(main_label));
/*Position the main label*/
lv_obj_align(main_label, LV_ALIGN_CENTER, 0, 0);
/*Shift the second label down and to the right by 2 pixel*/
lv_obj_align_to(shadow_label, main_label, LV_ALIGN_TOP_LEFT, 2, 2);
}
#endif
#
# Create a fake text shadow
#
# Create a style for the shadow
style_shadow = lv.style_t()
style_shadow.init()
style_shadow.set_text_opa(lv.OPA._30)
style_shadow.set_text_color(lv.color_black())
# Create a label for the shadow first (it's in the background)
shadow_label = lv.label(lv.scr_act())
shadow_label.add_style(style_shadow, 0)
# Create the main label
main_label = lv.label(lv.scr_act())
main_label.set_text("A simple method to create\n"
"shadows on a text.\n"
"It even works with\n\n"
"newlines and spaces.")
# Set the same text for the shadow label
shadow_label.set_text(lv.label.get_text(main_label))
# Position the main label
main_label.align(lv.ALIGN.CENTER, 0, 0)
# Shift the second label down and to the right by 2 pixel
shadow_label.align_to(main_label, lv.ALIGN.TOP_LEFT, 2, 2)
Show LTR, RTL and Chinese texts¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES && LV_FONT_DEJAVU_16_PERSIAN_HEBREW && LV_FONT_SIMSUN_16_CJK && LV_USE_BIDI
/**
* Show mixed LTR, RTL and Chinese label
*/
void lv_example_label_3(void)
{
lv_obj_t * ltr_label = lv_label_create(lv_scr_act());
lv_label_set_text(ltr_label, "In modern terminology, a microcontroller is similar to a system on a chip (SoC).");
lv_obj_set_style_text_font(ltr_label, &lv_font_montserrat_16, 0);
lv_obj_set_width(ltr_label, 310);
lv_obj_align(ltr_label, LV_ALIGN_TOP_LEFT, 5, 5);
lv_obj_t * rtl_label = lv_label_create(lv_scr_act());
lv_label_set_text(rtl_label,
"מעבד, או בשמו המלא יחידת עיבוד מרכזית (באנגלית: CPU - Central Processing Unit).");
lv_obj_set_style_base_dir(rtl_label, LV_BASE_DIR_RTL, 0);
lv_obj_set_style_text_font(rtl_label, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_width(rtl_label, 310);
lv_obj_align(rtl_label, LV_ALIGN_LEFT_MID, 5, 0);
lv_obj_t * cz_label = lv_label_create(lv_scr_act());
lv_label_set_text(cz_label,
"嵌入式系统（Embedded System），\n是一种嵌入机械或电气系统内部、具有专一功能和实时计算性能的计算机系统。");
lv_obj_set_style_text_font(cz_label, &lv_font_simsun_16_cjk, 0);
lv_obj_set_width(cz_label, 310);
lv_obj_align(cz_label, LV_ALIGN_BOTTOM_LEFT, 5, -5);
}
#endif
import fs_driver
#
# Show mixed LTR, RTL and Chinese label
#
ltr_label = lv.label(lv.scr_act())
ltr_label.set_text("In modern terminology, a microcontroller is similar to a system on a chip (SoC).")
# ltr_label.set_style_text_font(ltr_label, &lv_font_montserrat_16, 0);
fs_drv = lv.fs_drv_t()
fs_driver.fs_register(fs_drv, 'S')
try:
ltr_label.set_style_text_font(ltr_label, lv.font_montserrat_16, 0)
except:
font_montserrat_16 = lv.font_load("S:../../assets/font/montserrat-16.fnt")
ltr_label.set_style_text_font(font_montserrat_16, 0)
ltr_label.set_width(310)
ltr_label.align(lv.ALIGN.TOP_LEFT, 5, 5)
rtl_label = lv.label(lv.scr_act())
rtl_label.set_text("מעבד, או בשמו המלא יחידת עיבוד מרכזית (באנגלית: CPU - Central Processing Unit).")
rtl_label.set_style_base_dir(lv.BASE_DIR.RTL, 0)
rtl_label.set_style_text_font(lv.font_dejavu_16_persian_hebrew, 0)
rtl_label.set_width(310)
rtl_label.align(lv.ALIGN.LEFT_MID, 5, 0)
font_simsun_16_cjk = lv.font_load("S:../../assets/font/lv_font_simsun_16_cjk.fnt")
cz_label = lv.label(lv.scr_act())
cz_label.set_style_text_font(font_simsun_16_cjk, 0)
cz_label.set_text("嵌入式系统（Embedded System），\n是一种嵌入机械或电气系统内部、具有专一功能和实时计算性能的计算机系统。")
cz_label.set_width(310)
cz_label.align(lv.ALIGN.BOTTOM_LEFT, 5, -5)
Draw label with gradient color¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_USE_CANVAS && LV_BUILD_EXAMPLES && LV_DRAW_COMPLEX
#define MASK_WIDTH 100
#define MASK_HEIGHT 45
static void add_mask_event_cb(lv_event_t * e)
{
static lv_draw_mask_map_param_t m;
static int16_t mask_id;
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
lv_opa_t * mask_map = lv_event_get_user_data(e);
if(code == LV_EVENT_COVER_CHECK) {
lv_event_set_cover_res(e, LV_COVER_RES_MASKED);
}
else if(code == LV_EVENT_DRAW_MAIN_BEGIN) {
lv_draw_mask_map_init(&m, &obj->coords, mask_map);
mask_id = lv_draw_mask_add(&m, NULL);
}
else if(code == LV_EVENT_DRAW_MAIN_END) {
lv_draw_mask_free_param(&m);
lv_draw_mask_remove_id(mask_id);
}
}
/**
* Draw label with gradient color
*/
void lv_example_label_4(void)
{
/* Create the mask of a text by drawing it to a canvas*/
static lv_opa_t mask_map[MASK_WIDTH * MASK_HEIGHT];
/*Create a "8 bit alpha" canvas and clear it*/
lv_obj_t * canvas = lv_canvas_create(lv_scr_act());
lv_canvas_set_buffer(canvas, mask_map, MASK_WIDTH, MASK_HEIGHT, LV_IMG_CF_ALPHA_8BIT);
lv_canvas_fill_bg(canvas, lv_color_black(), LV_OPA_TRANSP);
/*Draw a label to the canvas. The result "image" will be used as mask*/
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.color = lv_color_white();
label_dsc.align = LV_TEXT_ALIGN_CENTER;
lv_canvas_draw_text(canvas, 5, 5, MASK_WIDTH, &label_dsc, "Text with gradient");
/*The mask is reads the canvas is not required anymore*/
lv_obj_del(canvas);
/* Create an object from where the text will be masked out.
* Now it's a rectangle with a gradient but it could be an image too*/
lv_obj_t * grad = lv_obj_create(lv_scr_act());
lv_obj_set_size(grad, MASK_WIDTH, MASK_HEIGHT);
lv_obj_center(grad);
lv_obj_set_style_bg_color(grad, lv_color_hex(0xff0000), 0);
lv_obj_set_style_bg_grad_color(grad, lv_color_hex(0x0000ff), 0);
lv_obj_set_style_bg_grad_dir(grad, LV_GRAD_DIR_HOR, 0);
lv_obj_add_event_cb(grad, add_mask_event_cb, LV_EVENT_ALL, mask_map);
}
#endif
Error encountered while trying to open /home/runner/work/lvgl/lvgl/examples/widgets/label/lv_example_label_4.py
Customize circular scrolling animation¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Show customizing the circular scrolling animation of a label with `LV_LABEL_LONG_SCROLL_CIRCULAR`
* long mode.
*/
void lv_example_label_5(void)
{
static lv_anim_t animation_template;
static lv_style_t label_style;
lv_anim_init(&animation_template);
lv_anim_set_delay(&animation_template, 1000); /*Wait 1 second to start the first scroll*/
lv_anim_set_repeat_delay(&animation_template,
3000); /*Repeat the scroll 3 seconds after the label scrolls back to the initial position*/
/*Initialize the label style with the animation template*/
lv_style_init(&label_style);
lv_style_set_anim(&label_style, &animation_template);
lv_obj_t * label1 = lv_label_create(lv_scr_act());
lv_label_set_long_mode(label1, LV_LABEL_LONG_SCROLL_CIRCULAR); /*Circular scroll*/
lv_obj_set_width(label1, 150);
lv_label_set_text(label1, "It is a circularly scrolling text. ");
lv_obj_align(label1, LV_ALIGN_CENTER, 0, 40);
lv_obj_add_style(label1, &label_style, LV_STATE_DEFAULT); /*Add the style to the label*/
}
#endif
#
# Show customizing the circular scrolling animation of a label with `LV_LABEL_LONG_SCROLL_CIRCULAR` long mode.
#
label1 = lv.label(lv.scr_act())
label1.set_long_mode(lv.label.LONG.SCROLL_CIRCULAR) # Circular scroll
label1.set_width(150)
label1.set_text("It is a circularly scrolling text. ")
label1.align(lv.ALIGN.CENTER, 0, 40)
LED¶
LED with custom style¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LED && LV_BUILD_EXAMPLES
/**
* Create LED's with different brightness and color
*/
void lv_example_led_1(void)
{
/*Create a LED and switch it OFF*/
lv_obj_t * led1 = lv_led_create(lv_scr_act());
lv_obj_align(led1, LV_ALIGN_CENTER, -80, 0);
lv_led_off(led1);
/*Copy the previous LED and set a brightness*/
lv_obj_t * led2 = lv_led_create(lv_scr_act());
lv_obj_align(led2, LV_ALIGN_CENTER, 0, 0);
lv_led_set_brightness(led2, 150);
lv_led_set_color(led2, lv_palette_main(LV_PALETTE_RED));
/*Copy the previous LED and switch it ON*/
lv_obj_t * led3 = lv_led_create(lv_scr_act());
lv_obj_align(led3, LV_ALIGN_CENTER, 80, 0);
lv_led_on(led3);
}
#endif
#
# Create LED's with different brightness and color
#
# Create a LED and switch it OFF
led1 = lv.led(lv.scr_act())
led1.align(lv.ALIGN.CENTER, -80, 0)
led1.off()
# Copy the previous LED and set a brightness
led2 = lv.led(lv.scr_act())
led2.align(lv.ALIGN.CENTER, 0, 0)
led2.set_brightness(150)
led2.set_color(lv.palette_main(lv.PALETTE.RED))
# Copy the previous LED and switch it ON
led3 = lv.led(lv.scr_act())
led3.align(lv.ALIGN.CENTER, 80, 0)
led3.on()
Line¶
Simple Line¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LINE && LV_BUILD_EXAMPLES
void lv_example_line_1(void)
{
/*Create an array for the points of the line*/
static lv_point_t line_points[] = { {5, 5}, {70, 70}, {120, 10}, {180, 60}, {240, 10} };
/*Create style*/
static lv_style_t style_line;
lv_style_init(&style_line);
lv_style_set_line_width(&style_line, 8);
lv_style_set_line_color(&style_line, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_line_rounded(&style_line, true);
/*Create a line and apply the new style*/
lv_obj_t * line1;
line1 = lv_line_create(lv_scr_act());
lv_line_set_points(line1, line_points, 5); /*Set the points*/
lv_obj_add_style(line1, &style_line, 0);
lv_obj_center(line1);
}
#endif
# Create an array for the points of the line
line_points = [ {"x":5, "y":5},
{"x":70, "y":70},
{"x":120, "y":10},
{"x":180, "y":60},
{"x":240, "y":10}]
# Create style
style_line = lv.style_t()
style_line.init()
style_line.set_line_width(8)
style_line.set_line_color(lv.palette_main(lv.PALETTE.BLUE))
style_line.set_line_rounded(True)
# Create a line and apply the new style
line1 = lv.line(lv.scr_act())
line1.set_points(line_points, 5) # Set the points
line1.add_style(style_line, 0)
line1.center()
List¶
Simple List¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LIST && LV_BUILD_EXAMPLES
static lv_obj_t * list1;
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
LV_LOG_USER("Clicked: %s", lv_list_get_btn_text(list1, obj));
}
}
void lv_example_list_1(void)
{
/*Create a list*/
list1 = lv_list_create(lv_scr_act());
lv_obj_set_size(list1, 180, 220);
lv_obj_center(list1);
/*Add buttons to the list*/
lv_obj_t * btn;
lv_list_add_text(list1, "File");
btn = lv_list_add_btn(list1, LV_SYMBOL_FILE, "New");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_DIRECTORY, "Open");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_SAVE, "Save");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_CLOSE, "Delete");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_EDIT, "Edit");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Connectivity");
btn = lv_list_add_btn(list1, LV_SYMBOL_BLUETOOTH, "Bluetooth");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_GPS, "Navigation");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_USB, "USB");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_BATTERY_FULL, "Battery");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Exit");
btn = lv_list_add_btn(list1, LV_SYMBOL_OK, "Apply");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_CLOSE, "Close");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.CLICKED:
print("Clicked: list1." + list1.get_btn_text(obj))
# Create a list
list1 = lv.list(lv.scr_act())
list1.set_size(180, 220)
list1.center()
# Add buttons to the list
list1.add_text("File")
btn_new = list1.add_btn(lv.SYMBOL.FILE, "New")
btn_new.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_open = list1.add_btn(lv.SYMBOL.DIRECTORY, "Open")
btn_open.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_save = list1.add_btn(lv.SYMBOL.SAVE, "Save")
btn_save.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_delete = list1.add_btn(lv.SYMBOL.CLOSE, "Delete")
btn_delete.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_edit = list1.add_btn(lv.SYMBOL.EDIT, "Edit")
btn_edit.add_event_cb(event_handler,lv.EVENT.ALL, None)
list1.add_text("Connectivity")
btn_bluetooth = list1.add_btn(lv.SYMBOL.BLUETOOTH, "Bluetooth")
btn_bluetooth.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_navig = list1.add_btn(lv.SYMBOL.GPS, "Navigation")
btn_navig.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_USB = list1.add_btn(lv.SYMBOL.USB, "USB")
btn_USB.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_battery = list1.add_btn(lv.SYMBOL.BATTERY_FULL, "Battery")
btn_battery.add_event_cb(event_handler,lv.EVENT.ALL, None)
list1.add_text("Exit")
btn_apply = list1.add_btn(lv.SYMBOL.OK, "Apply")
btn_apply.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_close = list1.add_btn(lv.SYMBOL.CLOSE, "Close")
btn_close.add_event_cb(event_handler,lv.EVENT.ALL, None)
Sorting a List using up and down buttons¶
C code
GitHub#include <stdlib.h>
#include "../../lv_examples.h"
#if LV_USE_LIST && LV_BUILD_EXAMPLES
static lv_obj_t * list1;
static lv_obj_t * list2;
static lv_obj_t * currentButton = NULL;
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
LV_LOG_USER("Clicked: %s", lv_list_get_btn_text(list1, obj));
if(currentButton == obj) {
currentButton = NULL;
}
else {
currentButton = obj;
}
lv_obj_t * parent = lv_obj_get_parent(obj);
uint32_t i;
for(i = 0; i < lv_obj_get_child_cnt(parent); i++) {
lv_obj_t * child = lv_obj_get_child(parent, i);
if(child == currentButton) {
lv_obj_add_state(child, LV_STATE_CHECKED);
}
else {
lv_obj_clear_state(child, LV_STATE_CHECKED);
}
}
}
}
static void event_handler_top(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_CLICKED) {
if(currentButton == NULL) return;
lv_obj_move_background(currentButton);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_up(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT)) {
if(currentButton == NULL) return;
uint32_t index = lv_obj_get_index(currentButton);
if(index <= 0) return;
lv_obj_move_to_index(currentButton, index - 1);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_center(lv_event_t * e)
{
const lv_event_code_t code = lv_event_get_code(e);
if((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT)) {
if(currentButton == NULL) return;
lv_obj_t * parent = lv_obj_get_parent(currentButton);
const uint32_t pos = lv_obj_get_child_cnt(parent) / 2;
lv_obj_move_to_index(currentButton, pos);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_dn(lv_event_t * e)
{
const lv_event_code_t code = lv_event_get_code(e);
if((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT)) {
if(currentButton == NULL) return;
const uint32_t index = lv_obj_get_index(currentButton);
lv_obj_move_to_index(currentButton, index + 1);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_bottom(lv_event_t * e)
{
const lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_CLICKED) {
if(currentButton == NULL) return;
lv_obj_move_foreground(currentButton);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_swap(lv_event_t * e)
{
const lv_event_code_t code = lv_event_get_code(e);
// lv_obj_t* obj = lv_event_get_target(e);
if((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT)) {
uint32_t cnt = lv_obj_get_child_cnt(list1);
for(int i = 0; i < 100; i++)
if(cnt > 1) {
lv_obj_t * obj = lv_obj_get_child(list1, rand() % cnt);
lv_obj_move_to_index(obj, rand() % cnt);
if(currentButton != NULL) {
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
}
}
void lv_example_list_2(void)
{
/*Create a list*/
list1 = lv_list_create(lv_scr_act());
lv_obj_set_size(list1, lv_pct(60), lv_pct(100));
lv_obj_set_style_pad_row(list1, 5, 0);
/*Add buttons to the list*/
lv_obj_t * btn;
int i;
for(i = 0; i < 15; i++) {
btn = lv_btn_create(list1);
lv_obj_set_width(btn, lv_pct(50));
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t * lab = lv_label_create(btn);
lv_label_set_text_fmt(lab, "Item %d", i);
}
/*Select the first button by default*/
currentButton = lv_obj_get_child(list1, 0);
lv_obj_add_state(currentButton, LV_STATE_CHECKED);
/*Create a second list with up and down buttons*/
list2 = lv_list_create(lv_scr_act());
lv_obj_set_size(list2, lv_pct(40), lv_pct(100));
lv_obj_align(list2, LV_ALIGN_TOP_RIGHT, 0, 0);
lv_obj_set_flex_flow(list2, LV_FLEX_FLOW_COLUMN);
btn = lv_list_add_btn(list2, NULL, "Top");
lv_obj_add_event_cb(btn, event_handler_top, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_UP, "Up");
lv_obj_add_event_cb(btn, event_handler_up, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_LEFT, "Center");
lv_obj_add_event_cb(btn, event_handler_center, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_DOWN, "Down");
lv_obj_add_event_cb(btn, event_handler_dn, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, NULL, "Bottom");
lv_obj_add_event_cb(btn, event_handler_bottom, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_SHUFFLE, "Shuffle");
lv_obj_add_event_cb(btn, event_handler_swap, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
}
#endif
import urandom
currentButton = None
list1 = None
def event_handler(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
if currentButton == obj:
currentButton = None
else:
currentButton = obj
parent = obj.get_parent()
for i in range( parent.get_child_cnt()):
child = parent.get_child(i)
if child == currentButton:
child.add_state(lv.STATE.CHECKED)
else:
child.clear_state(lv.STATE.CHECKED)
def event_handler_top(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
if currentButton == None:
return
currentButton.move_background()
currentButton.scroll_to_view( lv.ANIM.ON)
def event_handler_up(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
index = currentButton.get_index()
if index <= 0:
return
currentButton.move_to_index(index - 1)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_center(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
parent = currentButton.get_parent()
pos = parent.get_child_cnt() // 2
currentButton.move_to_index(pos)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_dn(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
index = currentButton.get_index()
currentButton.move_to_index(index + 1)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_bottom(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
currentButton.move_foreground()
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_swap(evt):
global currentButton
global list1
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
cnt = list1.get_child_cnt()
for i in range(100):
if cnt > 1:
obj = list1.get_child(urandom.getrandbits(32) % cnt )
obj.move_to_index(urandom.getrandbits(32) % cnt)
if currentButton != None:
currentButton.scroll_to_view(lv.ANIM.ON)
#Create a list with buttons that can be sorted
list1 = lv.list(lv.scr_act())
list1.set_size(lv.pct(60), lv.pct(100))
list1.set_style_pad_row( 5, 0)
for i in range(15):
btn = lv.btn(list1)
btn.set_width(lv.pct(100))
btn.add_event_cb( event_handler, lv.EVENT.CLICKED, None)
lab = lv.label(btn)
lab.set_text("Item " + str(i))
#Select the first button by default
currentButton = list1.get_child(0)
currentButton.add_state(lv.STATE.CHECKED)
#Create a second list with up and down buttons
list2 = lv.list(lv.scr_act())
list2.set_size(lv.pct(40), lv.pct(100))
list2.align(lv.ALIGN.TOP_RIGHT, 0, 0)
list2.set_flex_flow(lv.FLEX_FLOW.COLUMN)
btn = list2.add_btn(None, "Top")
btn.add_event_cb(event_handler_top, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.UP, "Up")
btn.add_event_cb(event_handler_up, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.LEFT, "Center")
btn.add_event_cb(event_handler_center, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.DOWN, "Down")
btn.add_event_cb(event_handler_dn, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(None, "Bottom")
btn.add_event_cb(event_handler_bottom, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.SHUFFLE, "Shuffle")
btn.add_event_cb(event_handler_swap, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
Menu¶
Meter¶
Simple meter¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES
static lv_obj_t * meter;
static void set_value(void * indic, int32_t v)
{
lv_meter_set_indicator_value(meter, indic, v);
}
/**
* A simple meter
*/
void lv_example_meter_1(void)
{
meter = lv_meter_create(lv_scr_act());
lv_obj_center(meter);
lv_obj_set_size(meter, 200, 200);
/*Add a scale first*/
lv_meter_scale_t * scale = lv_meter_add_scale(meter);
lv_meter_set_scale_ticks(meter, scale, 41, 2, 10, lv_palette_main(LV_PALETTE_GREY));
lv_meter_set_scale_major_ticks(meter, scale, 8, 4, 15, lv_color_black(), 10);
lv_meter_indicator_t * indic;
/*Add a blue arc to the start*/
indic = lv_meter_add_arc(meter, scale, 3, lv_palette_main(LV_PALETTE_BLUE), 0);
lv_meter_set_indicator_start_value(meter, indic, 0);
lv_meter_set_indicator_end_value(meter, indic, 20);
/*Make the tick lines blue at the start of the scale*/
indic = lv_meter_add_scale_lines(meter, scale, lv_palette_main(LV_PALETTE_BLUE), lv_palette_main(LV_PALETTE_BLUE),
false, 0);
lv_meter_set_indicator_start_value(meter, indic, 0);
lv_meter_set_indicator_end_value(meter, indic, 20);
/*Add a red arc to the end*/
indic = lv_meter_add_arc(meter, scale, 3, lv_palette_main(LV_PALETTE_RED), 0);
lv_meter_set_indicator_start_value(meter, indic, 80);
lv_meter_set_indicator_end_value(meter, indic, 100);
/*Make the tick lines red at the end of the scale*/
indic = lv_meter_add_scale_lines(meter, scale, lv_palette_main(LV_PALETTE_RED), lv_palette_main(LV_PALETTE_RED), false,
0);
lv_meter_set_indicator_start_value(meter, indic, 80);
lv_meter_set_indicator_end_value(meter, indic, 100);
/*Add a needle line indicator*/
indic = lv_meter_add_needle_line(meter, scale, 4, lv_palette_main(LV_PALETTE_GREY), -10);
/*Create an animation to set the value*/
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_exec_cb(&a, set_value);
lv_anim_set_var(&a, indic);
lv_anim_set_values(&a, 0, 100);
lv_anim_set_time(&a, 2000);
lv_anim_set_repeat_delay(&a, 100);
lv_anim_set_playback_time(&a, 500);
lv_anim_set_playback_delay(&a, 100);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver
def set_value(indic, v):
meter.set_indicator_value(indic, v)
#
# A simple meter
#
meter = lv.meter(lv.scr_act())
meter.center()
meter.set_size(200, 200)
# Add a scale first
scale = meter.add_scale()
meter.set_scale_ticks(scale, 51, 2, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_major_ticks(scale, 10, 4, 15, lv.color_black(), 10)
indic = lv.meter_indicator_t()
# Add a blue arc to the start
indic = meter.add_arc(scale, 3, lv.palette_main(lv.PALETTE.BLUE), 0)
meter.set_indicator_start_value(indic, 0)
meter.set_indicator_end_value(indic, 20)
# Make the tick lines blue at the start of the scale
indic = meter.add_scale_lines(scale, lv.palette_main(lv.PALETTE.BLUE), lv.palette_main(lv.PALETTE.BLUE), False, 0)
meter.set_indicator_start_value(indic, 0)
meter.set_indicator_end_value(indic, 20)
# Add a red arc to the end
indic = meter.add_arc(scale, 3, lv.palette_main(lv.PALETTE.RED), 0)
meter.set_indicator_start_value(indic, 80)
meter.set_indicator_end_value(indic, 100)
# Make the tick lines red at the end of the scale
indic = meter.add_scale_lines(scale, lv.palette_main(lv.PALETTE.RED), lv.palette_main(lv.PALETTE.RED), False, 0)
meter.set_indicator_start_value(indic, 80)
meter.set_indicator_end_value(indic, 100)
# Add a needle line indicator
indic = meter.add_needle_line(scale, 4, lv.palette_main(lv.PALETTE.GREY), -10)
# Create an animation to set the value
a = lv.anim_t()
a.init()
a.set_var(indic)
a.set_values(0, 100)
a.set_time(2000)
a.set_repeat_delay(100)
a.set_playback_time(500)
a.set_playback_delay(100)
a.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a.set_custom_exec_cb(lambda a,val: set_value(indic,val))
lv.anim_t.start(a)
A meter with multiple arcs¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES
static lv_obj_t * meter;
static void set_value(void * indic, int32_t v)
{
lv_meter_set_indicator_end_value(meter, indic, v);
}
/**
* A meter with multiple arcs
*/
void lv_example_meter_2(void)
{
meter = lv_meter_create(lv_scr_act());
lv_obj_center(meter);
lv_obj_set_size(meter, 200, 200);
/*Remove the circle from the middle*/
lv_obj_remove_style(meter, NULL, LV_PART_INDICATOR);
/*Add a scale first*/
lv_meter_scale_t * scale = lv_meter_add_scale(meter);
lv_meter_set_scale_ticks(meter, scale, 11, 2, 10, lv_palette_main(LV_PALETTE_GREY));
lv_meter_set_scale_major_ticks(meter, scale, 1, 2, 30, lv_color_hex3(0xeee), 15);
lv_meter_set_scale_range(meter, scale, 0, 100, 270, 90);
/*Add a three arc indicator*/
lv_meter_indicator_t * indic1 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_RED), 0);
lv_meter_indicator_t * indic2 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_GREEN), -10);
lv_meter_indicator_t * indic3 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_BLUE), -20);
/*Create an animation to set the value*/
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_exec_cb(&a, set_value);
lv_anim_set_values(&a, 0, 100);
lv_anim_set_repeat_delay(&a, 100);
lv_anim_set_playback_delay(&a, 100);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_time(&a, 2000);
lv_anim_set_playback_time(&a, 500);
lv_anim_set_var(&a, indic1);
lv_anim_start(&a);
lv_anim_set_time(&a, 1000);
lv_anim_set_playback_time(&a, 1000);
lv_anim_set_var(&a, indic2);
lv_anim_start(&a);
lv_anim_set_time(&a, 1000);
lv_anim_set_playback_time(&a, 2000);
lv_anim_set_var(&a, indic3);
lv_anim_start(&a);
}
#endif
#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver
def set_value(indic,v):
meter.set_indicator_end_value(indic, v)
#
# A meter with multiple arcs
#
meter = lv.meter(lv.scr_act())
meter.center()
meter.set_size(200, 200)
# Remove the circle from the middle
meter.remove_style(None, lv.PART.INDICATOR)
# Add a scale first
scale = meter.add_scale()
meter.set_scale_ticks(scale, 11, 2, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_major_ticks(scale, 1, 2, 30, lv.color_hex3(0xeee), 10)
meter.set_scale_range(scale, 0, 100, 270, 90)
# Add a three arc indicator
indic1 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.RED), 0)
indic2 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.GREEN), -10)
indic3 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.BLUE), -20)
# Create an animation to set the value
a1 = lv.anim_t()
a1.init()
a1.set_values(0, 100)
a1.set_time(2000)
a1.set_repeat_delay(100)
a1.set_playback_delay(100)
a1.set_playback_time(500)
a1.set_var(indic1)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a1.set_custom_exec_cb(lambda a,val: set_value(indic1,val))
lv.anim_t.start(a1)
a2 = lv.anim_t()
a2.init()
a2.set_values(0, 100)
a2.set_time(1000)
a2.set_repeat_delay(100)
a2.set_playback_delay(100)
a2.set_playback_time(1000)
a2.set_var(indic2)
a2.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a2.set_custom_exec_cb(lambda a,val: set_value(indic2,val))
lv.anim_t.start(a2)
a3 = lv.anim_t()
a3.init()
a3.set_values(0, 100)
a3.set_time(1000)
a3.set_repeat_delay(100)
a3.set_playback_delay(100)
a3.set_playback_time(2000)
a3.set_var(indic3)
a3.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a3.set_custom_exec_cb(lambda a,val: set_value(indic3,val))
lv.anim_t.start(a3)
A clock from a meter¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES
static lv_obj_t * meter;
static void set_value(void * indic, int32_t v)
{
lv_meter_set_indicator_end_value(meter, indic, v);
}
/**
* A clock from a meter
*/
void lv_example_meter_3(void)
{
meter = lv_meter_create(lv_scr_act());
lv_obj_set_size(meter, 220, 220);
lv_obj_center(meter);
/*Create a scale for the minutes*/
/*61 ticks in a 360 degrees range (the last and the first line overlaps)*/
lv_meter_scale_t * scale_min = lv_meter_add_scale(meter);
lv_meter_set_scale_ticks(meter, scale_min, 61, 1, 10, lv_palette_main(LV_PALETTE_GREY));
lv_meter_set_scale_range(meter, scale_min, 0, 60, 360, 270);
/*Create another scale for the hours. It's only visual and contains only major ticks*/
lv_meter_scale_t * scale_hour = lv_meter_add_scale(meter);
lv_meter_set_scale_ticks(meter, scale_hour, 12, 0, 0, lv_palette_main(LV_PALETTE_GREY)); /*12 ticks*/
lv_meter_set_scale_major_ticks(meter, scale_hour, 1, 2, 20, lv_color_black(), 10); /*Every tick is major*/
lv_meter_set_scale_range(meter, scale_hour, 1, 12, 330, 300); /*[1..12] values in an almost full circle*/
LV_IMG_DECLARE(img_hand)
/*Add a the hands from images*/
lv_meter_indicator_t * indic_min = lv_meter_add_needle_img(meter, scale_min, &img_hand, 5, 5);
lv_meter_indicator_t * indic_hour = lv_meter_add_needle_img(meter, scale_min, &img_hand, 5, 5);
/*Create an animation to set the value*/
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_exec_cb(&a, set_value);
lv_anim_set_values(&a, 0, 60);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_time(&a, 2000); /*2 sec for 1 turn of the minute hand (1 hour)*/
lv_anim_set_var(&a, indic_min);
lv_anim_start(&a);
lv_anim_set_var(&a, indic_hour);
lv_anim_set_time(&a, 24000); /*24 sec for 1 turn of the hour hand*/
lv_anim_set_values(&a, 0, 60);
lv_anim_start(&a);
}
#endif
#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver
from imagetools import get_png_info, open_png
# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png
# Create an image from the png file
try:
with open('../../assets/img_hand_min.png','rb') as f:
img_hand_min_data = f.read()
except:
print("Could not find img_hand_min.png")
sys.exit()
img_hand_min_dsc = lv.img_dsc_t({
'data_size': len(img_hand_min_data),
'data': img_hand_min_data
})
# Create an image from the png file
try:
with open('../../assets/img_hand_hour.png','rb') as f:
img_hand_hour_data = f.read()
except:
print("Could not find img_hand_hour.png")
sys.exit()
img_hand_hour_dsc = lv.img_dsc_t({
'data_size': len(img_hand_hour_data),
'data': img_hand_hour_data
})
def set_value(indic, v):
meter.set_indicator_value(indic, v)
#
# A clock from a meter
#
meter = lv.meter(lv.scr_act())
meter.set_size(220, 220)
meter.center()
# Create a scale for the minutes
# 61 ticks in a 360 degrees range (the last and the first line overlaps)
scale_min = meter.add_scale()
meter.set_scale_ticks(scale_min, 61, 1, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_range(scale_min, 0, 60, 360, 270)
# Create another scale for the hours. It's only visual and contains only major ticks
scale_hour = meter.add_scale()
meter.set_scale_ticks(scale_hour, 12, 0, 0, lv.palette_main(lv.PALETTE.GREY)) # 12 ticks
meter.set_scale_major_ticks(scale_hour, 1, 2, 20, lv.color_black(), 10) # Every tick is major
meter.set_scale_range(scale_hour, 1, 12, 330, 300) # [1..12] values in an almost full circle
# LV_IMG_DECLARE(img_hand)
# Add the hands from images
indic_min = meter.add_needle_img(scale_min, img_hand_min_dsc, 5, 5)
indic_hour = meter.add_needle_img(scale_min, img_hand_hour_dsc, 5, 5)
# Create an animation to set the value
a1 = lv.anim_t()
a1.init()
a1.set_values(0, 60)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a1.set_time(2000) # 2 sec for 1 turn of the minute hand (1 hour)
a1.set_var(indic_min)
a1.set_custom_exec_cb(lambda a1,val: set_value(indic_min,val))
lv.anim_t.start(a1)
a2 = lv.anim_t()
a2.init()
a2.set_var(indic_hour)
a2.set_time(24000) # 24 sec for 1 turn of the hour hand
a2.set_values(0, 60)
a2.set_custom_exec_cb(lambda a2,val: set_value(indic_hour,val))
lv.anim_t.start(a2)
Pie chart¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES
/**
* Create a pie chart
*/
void lv_example_meter_4(void)
{
lv_obj_t * meter = lv_meter_create(lv_scr_act());
/*Remove the background and the circle from the middle*/
lv_obj_remove_style(meter, NULL, LV_PART_MAIN);
lv_obj_remove_style(meter, NULL, LV_PART_INDICATOR);
lv_obj_set_size(meter, 200, 200);
lv_obj_center(meter);
/*Add a scale first with no ticks.*/
lv_meter_scale_t * scale = lv_meter_add_scale(meter);
lv_meter_set_scale_ticks(meter, scale, 0, 0, 0, lv_color_black());
lv_meter_set_scale_range(meter, scale, 0, 100, 360, 0);
/*Add a three arc indicator*/
lv_coord_t indic_w = 100;
lv_meter_indicator_t * indic1 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_ORANGE), 0);
lv_meter_set_indicator_start_value(meter, indic1, 0);
lv_meter_set_indicator_end_value(meter, indic1, 40);
lv_meter_indicator_t * indic2 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_YELLOW), 0);
lv_meter_set_indicator_start_value(meter, indic2, 40); /*Start from the previous*/
lv_meter_set_indicator_end_value(meter, indic2, 80);
lv_meter_indicator_t * indic3 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_DEEP_ORANGE), 0);
lv_meter_set_indicator_start_value(meter, indic3, 80); /*Start from the previous*/
lv_meter_set_indicator_end_value(meter, indic3, 100);
}
#endif
#
# Create a pie chart
#
meter = lv.meter(lv.scr_act())
# Remove the background and the circle from the middle
meter.remove_style(None, lv.PART.MAIN)
meter.remove_style(None, lv.PART.INDICATOR)
meter.set_size(200, 200)
meter.center()
# Add a scale first with no ticks.
scale = meter.add_scale()
meter.set_scale_ticks(scale, 0, 0, 0, lv.color_black())
meter.set_scale_range(scale, 0, 100, 360, 0)
# Add a three arc indicator*
indic_w = 100
indic1 = meter.add_arc(scale, indic_w,lv.palette_main(lv.PALETTE.ORANGE), 0)
meter.set_indicator_start_value(indic1, 0)
meter.set_indicator_end_value(indic1, 40)
indic2 = meter.add_arc(scale, indic_w, lv.palette_main(lv.PALETTE.YELLOW), 0)
meter.set_indicator_start_value(indic2, 40) # Start from the previous
meter.set_indicator_end_value(indic2, 80)
indic3 = meter.add_arc(scale, indic_w, lv.palette_main(lv.PALETTE.DEEP_ORANGE), 0)
meter.set_indicator_start_value(indic3, 80) # Start from the previous
meter.set_indicator_end_value(indic3, 100)
Message box¶
Simple Message box¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_MSGBOX && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_current_target(e);
LV_LOG_USER("Button %s clicked", lv_msgbox_get_active_btn_text(obj));
}
void lv_example_msgbox_1(void)
{
static const char * btns[] = {"Apply", "Close", ""};
lv_obj_t * mbox1 = lv_msgbox_create(NULL, "Hello", "This is a message box with two buttons.", btns, true);
lv_obj_add_event_cb(mbox1, event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_center(mbox1);
}
#endif
def event_cb(e):
mbox = e.get_current_target()
print("Button %s clicked" % mbox.get_active_btn_text())
btns = ["Apply", "Close", ""]
mbox1 = lv.msgbox(lv.scr_act(), "Hello", "This is a message box with two buttons.", btns, True)
mbox1.add_event_cb(event_cb, lv.EVENT.VALUE_CHANGED, None)
mbox1.center()
Roller¶
Simple Roller¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_roller_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Selected month: %s\n", buf);
}
}
/**
* An infinite roller with the name of the months
*/
void lv_example_roller_1(void)
{
lv_obj_t * roller1 = lv_roller_create(lv_scr_act());
lv_roller_set_options(roller1,
"January\n"
"February\n"
"March\n"
"April\n"
"May\n"
"June\n"
"July\n"
"August\n"
"September\n"
"October\n"
"November\n"
"December",
LV_ROLLER_MODE_INFINITE);
lv_roller_set_visible_row_count(roller1, 4);
lv_obj_center(roller1);
lv_obj_add_event_cb(roller1, event_handler, LV_EVENT_ALL, NULL);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
option = " "*10
obj.get_selected_str(option, len(option))
print("Selected month: " + option.strip())
#
# An infinite roller with the name of the months
#
roller1 = lv.roller(lv.scr_act())
roller1.set_options("\n".join([
"January",
"February",
"March",
"April",
"May",
"June",
"July",
"August",
"September",
"October",
"November",
"December"]),lv.roller.MODE.INFINITE)
roller1.set_visible_row_count(4)
roller1.center()
roller1.add_event_cb(event_handler, lv.EVENT.ALL, None)
Styling the roller¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_FONT_MONTSERRAT_22 && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_roller_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Selected value: %s", buf);
}
}
/**
* Roller with various alignments and larger text in the selected area
*/
void lv_example_roller_2(void)
{
/*A style to make the selected option larger*/
static lv_style_t style_sel;
lv_style_init(&style_sel);
lv_style_set_text_font(&style_sel, &lv_font_montserrat_22);
const char * opts = "1\n2\n3\n4\n5\n6\n7\n8\n9\n10";
lv_obj_t * roller;
/*A roller on the left with left aligned text, and custom width*/
roller = lv_roller_create(lv_scr_act());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 2);
lv_obj_set_width(roller, 100);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_set_style_text_align(roller, LV_TEXT_ALIGN_LEFT, 0);
lv_obj_align(roller, LV_ALIGN_LEFT_MID, 10, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 2, LV_ANIM_OFF);
/*A roller on the middle with center aligned text, and auto (default) width*/
roller = lv_roller_create(lv_scr_act());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 3);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_align(roller, LV_ALIGN_CENTER, 0, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 5, LV_ANIM_OFF);
/*A roller on the right with right aligned text, and custom width*/
roller = lv_roller_create(lv_scr_act());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 4);
lv_obj_set_width(roller, 80);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_set_style_text_align(roller, LV_TEXT_ALIGN_RIGHT, 0);
lv_obj_align(roller, LV_ALIGN_RIGHT_MID, -10, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 8, LV_ANIM_OFF);
}
#endif
import fs_driver
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
option = " "*10
obj.get_selected_str(option, len(option))
print("Selected value: %s\n" + option.strip())
#
# Roller with various alignments and larger text in the selected area
#
# A style to make the selected option larger
style_sel = lv.style_t()
style_sel.init()
try:
style_sel.set_text_font(lv.font_montserrat_22)
except:
fs_drv = lv.fs_drv_t()
fs_driver.fs_register(fs_drv, 'S')
print("montserrat-22 not enabled in lv_conf.h, dynamically loading the font")
font_montserrat_22 = lv.font_load("S:" + "../../assets/font/montserrat-22.fnt")
style_sel.set_text_font(font_montserrat_22)
opts = "\n".join(["1","2","3","4","5","6","7","8","9","10"])
# A roller on the left with left aligned text, and custom width
roller = lv.roller(lv.scr_act())
roller.set_options(opts, lv.roller.MODE.NORMAL)
roller.set_visible_row_count(2)
roller.set_width(100)
roller.add_style(style_sel, lv.PART.SELECTED)
roller.set_style_text_align(lv.TEXT_ALIGN.LEFT, 0)
roller.align(lv.ALIGN.LEFT_MID, 10, 0)
roller.add_event_cb(event_handler, lv.EVENT.ALL, None)
roller.set_selected(2, lv.ANIM.OFF)
# A roller in the middle with center aligned text, and auto (default) width
roller = lv.roller(lv.scr_act())
roller.set_options(opts, lv.roller.MODE.NORMAL)
roller.set_visible_row_count(3)
roller.add_style(style_sel, lv.PART.SELECTED)
roller.align(lv.ALIGN.CENTER, 0, 0)
roller.add_event_cb(event_handler, lv.EVENT.ALL, None)
roller.set_selected(5, lv.ANIM.OFF)
# A roller on the right with right aligned text, and custom width
roller = lv.roller(lv.scr_act())
roller.set_options(opts, lv.roller.MODE.NORMAL)
roller.set_visible_row_count(4)
roller.set_width(80)
roller.add_style(style_sel, lv.PART.SELECTED)
roller.set_style_text_align(lv.TEXT_ALIGN.RIGHT, 0)
roller.align(lv.ALIGN.RIGHT_MID, -10, 0)
roller.add_event_cb(event_handler, lv.EVENT.ALL, None)
roller.set_selected(8, lv.ANIM.OFF)
add fade mask to roller¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_DRAW_COMPLEX && LV_BUILD_EXAMPLES
static void mask_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
static int16_t mask_top_id = -1;
static int16_t mask_bottom_id = -1;
if(code == LV_EVENT_COVER_CHECK) {
lv_event_set_cover_res(e, LV_COVER_RES_MASKED);
}
else if(code == LV_EVENT_DRAW_MAIN_BEGIN) {
/* add mask */
const lv_font_t * font = lv_obj_get_style_text_font(obj, LV_PART_MAIN);
lv_coord_t line_space = lv_obj_get_style_text_line_space(obj, LV_PART_MAIN);
lv_coord_t font_h = lv_font_get_line_height(font);
lv_area_t roller_coords;
lv_obj_get_coords(obj, &roller_coords);
lv_area_t rect_area;
rect_area.x1 = roller_coords.x1;
rect_area.x2 = roller_coords.x2;
rect_area.y1 = roller_coords.y1;
rect_area.y2 = roller_coords.y1 + (lv_obj_get_height(obj) - font_h - line_space) / 2;
lv_draw_mask_fade_param_t * fade_mask_top = lv_mem_buf_get(sizeof(lv_draw_mask_fade_param_t));
lv_draw_mask_fade_init(fade_mask_top, &rect_area, LV_OPA_TRANSP, rect_area.y1, LV_OPA_COVER, rect_area.y2);
mask_top_id = lv_draw_mask_add(fade_mask_top, NULL);
rect_area.y1 = rect_area.y2 + font_h + line_space - 1;
rect_area.y2 = roller_coords.y2;
lv_draw_mask_fade_param_t * fade_mask_bottom = lv_mem_buf_get(sizeof(lv_draw_mask_fade_param_t));
lv_draw_mask_fade_init(fade_mask_bottom, &rect_area, LV_OPA_COVER, rect_area.y1, LV_OPA_TRANSP, rect_area.y2);
mask_bottom_id = lv_draw_mask_add(fade_mask_bottom, NULL);
}
else if(code == LV_EVENT_DRAW_POST_END) {
lv_draw_mask_fade_param_t * fade_mask_top = lv_draw_mask_remove_id(mask_top_id);
lv_draw_mask_fade_param_t * fade_mask_bottom = lv_draw_mask_remove_id(mask_bottom_id);
lv_draw_mask_free_param(fade_mask_top);
lv_draw_mask_free_param(fade_mask_bottom);
lv_mem_buf_release(fade_mask_top);
lv_mem_buf_release(fade_mask_bottom);
mask_top_id = -1;
mask_bottom_id = -1;
}
}
/**
* Add a fade mask to roller.
*/
void lv_example_roller_3(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_bg_color(&style, lv_color_black());
lv_style_set_text_color(&style, lv_color_white());
lv_style_set_border_width(&style, 0);
lv_style_set_pad_all(&style, 0);
lv_obj_add_style(lv_scr_act(), &style, 0);
lv_obj_t * roller1 = lv_roller_create(lv_scr_act());
lv_obj_add_style(roller1, &style, 0);
lv_obj_set_style_bg_opa(roller1, LV_OPA_TRANSP, LV_PART_SELECTED);
#if LV_FONT_MONTSERRAT_22
lv_obj_set_style_text_font(roller1, &lv_font_montserrat_22, LV_PART_SELECTED);
#endif
lv_roller_set_options(roller1,
"January\n"
"February\n"
"March\n"
"April\n"
"May\n"
"June\n"
"July\n"
"August\n"
"September\n"
"October\n"
"November\n"
"December",
LV_ROLLER_MODE_NORMAL);
lv_obj_center(roller1);
lv_roller_set_visible_row_count(roller1, 3);
lv_obj_add_event_cb(roller1, mask_event_cb, LV_EVENT_ALL, NULL);
}
#endif
import fs_driver
import sys
class Lv_Roller_3():
def __init__(self):
self.mask_top_id = -1
self.mask_bottom_id = -1
#
# Add a fade mask to roller.
#
style = lv.style_t()
style.init()
style.set_bg_color(lv.color_black())
style.set_text_color(lv.color_white())
lv.scr_act().add_style(style, 0)
roller1 = lv.roller(lv.scr_act())
roller1.add_style(style, 0)
roller1.set_style_border_width(0, 0)
roller1.set_style_pad_all(0, 0)
roller1.set_style_bg_opa(lv.OPA.TRANSP, lv.PART.SELECTED)
#if LV_FONT_MONTSERRAT_22
# lv_obj_set_style_text_font(roller1, &lv_font_montserrat_22, LV_PART_SELECTED);
#endif
try:
roller1.set_style_text_font(lv.font_montserrat_22,lv.PART.SELECTED)
except:
fs_drv = lv.fs_drv_t()
fs_driver.fs_register(fs_drv, 'S')
print("montserrat-22 not enabled in lv_conf.h, dynamically loading the font")
font_montserrat_22 = lv.font_load("S:" + "../../assets/font/montserrat-22.fnt")
roller1.set_style_text_font(font_montserrat_22,lv.PART.SELECTED)
roller1.set_options("\n".join([
"January",
"February",
"March",
"April",
"May",
"June",
"July",
"August",
"September",
"October",
"November",
"December"]),lv.roller.MODE.NORMAL)
roller1.center()
roller1.set_visible_row_count(3)
roller1.add_event_cb(self.mask_event_cb, lv.EVENT.ALL, None)
def mask_event_cb(self,e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.COVER_CHECK:
e.set_cover_res(lv.COVER_RES.MASKED)
elif code == lv.EVENT.DRAW_MAIN_BEGIN:
# add mask
font = obj.get_style_text_font(lv.PART.MAIN)
line_space = obj.get_style_text_line_space(lv.PART.MAIN)
font_h = font.get_line_height()
roller_coords = lv.area_t()
obj.get_coords(roller_coords)
rect_area = lv.area_t()
rect_area.x1 = roller_coords.x1
rect_area.x2 = roller_coords.x2
rect_area.y1 = roller_coords.y1
rect_area.y2 = roller_coords.y1 + (obj.get_height() - font_h - line_space) // 2
fade_mask_top = lv.draw_mask_fade_param_t()
fade_mask_top.init(rect_area, lv.OPA.TRANSP, rect_area.y1, lv.OPA.COVER, rect_area.y2)
self.mask_top_id = lv.draw_mask_add(fade_mask_top,None)
rect_area.y1 = rect_area.y2 + font_h + line_space - 1
rect_area.y2 = roller_coords.y2
fade_mask_bottom = lv.draw_mask_fade_param_t()
fade_mask_bottom.init(rect_area, lv.OPA.COVER, rect_area.y1, lv.OPA.TRANSP, rect_area.y2)
self.mask_bottom_id = lv.draw_mask_add(fade_mask_bottom, None)
elif code == lv.EVENT.DRAW_POST_END:
fade_mask_top = lv.draw_mask_remove_id(self.mask_top_id)
fade_mask_bottom = lv.draw_mask_remove_id(self.mask_bottom_id)
# Remove the masks
lv.draw_mask_remove_id(self.mask_top_id)
lv.draw_mask_remove_id(self.mask_bottom_id)
self.mask_top_id = -1
self.mask_bottom_id = -1
roller3 = Lv_Roller_3()
Slider¶
Simple Slider¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
static void slider_event_cb(lv_event_t * e);
static lv_obj_t * slider_label;
/**
* A default slider with a label displaying the current value
*/
void lv_example_slider_1(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_scr_act());
lv_obj_center(slider);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
/*Create a label below the slider*/
slider_label = lv_label_create(lv_scr_act());
lv_label_set_text(slider_label, "0%");
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
static void slider_event_cb(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
char buf[8];
lv_snprintf(buf, sizeof(buf), "%d%%", (int)lv_slider_get_value(slider));
lv_label_set_text(slider_label, buf);
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
#endif
#
# A default slider with a label displaying the current value
#
def slider_event_cb(e):
slider = e.get_target()
slider_label.set_text("{:d}%".format(slider.get_value()))
slider_label.align_to(slider, lv.ALIGN.OUT_BOTTOM_MID, 0, 10)
# Create a slider in the center of the display
slider = lv.slider(lv.scr_act())
slider.center()
slider.add_event_cb(slider_event_cb, lv.EVENT.VALUE_CHANGED, None)
# Create a label below the slider
slider_label = lv.label(lv.scr_act())
slider_label.set_text("0%")
slider_label.align_to(slider, lv.ALIGN.OUT_BOTTOM_MID, 0, 10)
Slider with custom style¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
/**
* Show how to style a slider.
*/
void lv_example_slider_2(void)
{
/*Create a transition*/
static const lv_style_prop_t props[] = {LV_STYLE_BG_COLOR, 0};
static lv_style_transition_dsc_t transition_dsc;
lv_style_transition_dsc_init(&transition_dsc, props, lv_anim_path_linear, 300, 0, NULL);
static lv_style_t style_main;
static lv_style_t style_indicator;
static lv_style_t style_knob;
static lv_style_t style_pressed_color;
lv_style_init(&style_main);
lv_style_set_bg_opa(&style_main, LV_OPA_COVER);
lv_style_set_bg_color(&style_main, lv_color_hex3(0xbbb));
lv_style_set_radius(&style_main, LV_RADIUS_CIRCLE);
lv_style_set_pad_ver(&style_main, -2); /*Makes the indicator larger*/
lv_style_init(&style_indicator);
lv_style_set_bg_opa(&style_indicator, LV_OPA_COVER);
lv_style_set_bg_color(&style_indicator, lv_palette_main(LV_PALETTE_CYAN));
lv_style_set_radius(&style_indicator, LV_RADIUS_CIRCLE);
lv_style_set_transition(&style_indicator, &transition_dsc);
lv_style_init(&style_knob);
lv_style_set_bg_opa(&style_knob, LV_OPA_COVER);
lv_style_set_bg_color(&style_knob, lv_palette_main(LV_PALETTE_CYAN));
lv_style_set_border_color(&style_knob, lv_palette_darken(LV_PALETTE_CYAN, 3));
lv_style_set_border_width(&style_knob, 2);
lv_style_set_radius(&style_knob, LV_RADIUS_CIRCLE);
lv_style_set_pad_all(&style_knob, 6); /*Makes the knob larger*/
lv_style_set_transition(&style_knob, &transition_dsc);
lv_style_init(&style_pressed_color);
lv_style_set_bg_color(&style_pressed_color, lv_palette_darken(LV_PALETTE_CYAN, 2));
/*Create a slider and add the style*/
lv_obj_t * slider = lv_slider_create(lv_scr_act());
lv_obj_remove_style_all(slider); /*Remove the styles coming from the theme*/
lv_obj_add_style(slider, &style_main, LV_PART_MAIN);
lv_obj_add_style(slider, &style_indicator, LV_PART_INDICATOR);
lv_obj_add_style(slider, &style_pressed_color, LV_PART_INDICATOR | LV_STATE_PRESSED);
lv_obj_add_style(slider, &style_knob, LV_PART_KNOB);
lv_obj_add_style(slider, &style_pressed_color, LV_PART_KNOB | LV_STATE_PRESSED);
lv_obj_center(slider);
}
#endif
#
# Show how to style a slider.
#
# Create a transition
props = [lv.STYLE.BG_COLOR, 0]
transition_dsc = lv.style_transition_dsc_t()
transition_dsc.init(props, lv.anim_t.path_linear, 300, 0, None)
style_main = lv.style_t()
style_indicator = lv.style_t()
style_knob = lv.style_t()
style_pressed_color = lv.style_t()
style_main.init()
style_main.set_bg_opa(lv.OPA.COVER)
style_main.set_bg_color(lv.color_hex3(0xbbb))
style_main.set_radius(lv.RADIUS.CIRCLE)
style_main.set_pad_ver(-2) # Makes the indicator larger
style_indicator.init()
style_indicator.set_bg_opa(lv.OPA.COVER)
style_indicator.set_bg_color(lv.palette_main(lv.PALETTE.CYAN))
style_indicator.set_radius(lv.RADIUS.CIRCLE)
style_indicator.set_transition(transition_dsc)
style_knob.init()
style_knob.set_bg_opa(lv.OPA.COVER)
style_knob.set_bg_color(lv.palette_main(lv.PALETTE.CYAN))
style_knob.set_border_color(lv.palette_darken(lv.PALETTE.CYAN, 3))
style_knob.set_border_width(2)
style_knob.set_radius(lv.RADIUS.CIRCLE)
style_knob.set_pad_all(6) # Makes the knob larger
style_knob.set_transition(transition_dsc)
style_pressed_color.init()
style_pressed_color.set_bg_color(lv.palette_darken(lv.PALETTE.CYAN, 2))
# Create a slider and add the style
slider = lv.slider(lv.scr_act())
slider.remove_style_all() # Remove the styles coming from the theme
slider.add_style(style_main, lv.PART.MAIN)
slider.add_style(style_indicator, lv.PART.INDICATOR)
slider.add_style(style_pressed_color, lv.PART.INDICATOR | lv.STATE.PRESSED)
slider.add_style(style_knob, lv.PART.KNOB)
slider.add_style(style_pressed_color, lv.PART.KNOB | lv.STATE.PRESSED)
slider.center()
Slider with extended drawer¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
static void slider_event_cb(lv_event_t * e);
/**
* Show the current value when the slider is pressed by extending the drawer
*
*/
void lv_example_slider_3(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider;
slider = lv_slider_create(lv_scr_act());
lv_obj_center(slider);
lv_slider_set_mode(slider, LV_SLIDER_MODE_RANGE);
lv_slider_set_value(slider, 70, LV_ANIM_OFF);
lv_slider_set_left_value(slider, 20, LV_ANIM_OFF);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_ALL, NULL);
lv_obj_refresh_ext_draw_size(slider);
}
static void slider_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
/*Provide some extra space for the value*/
if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
lv_event_set_ext_draw_size(e, 50);
}
else if(code == LV_EVENT_DRAW_PART_END) {
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
if(dsc->part == LV_PART_INDICATOR) {
char buf[16];
lv_snprintf(buf, sizeof(buf), "%d - %d", (int)lv_slider_get_left_value(obj), (int)lv_slider_get_value(obj));
lv_point_t label_size;
lv_txt_get_size(&label_size, buf, LV_FONT_DEFAULT, 0, 0, LV_COORD_MAX, 0);
lv_area_t label_area;
label_area.x1 = dsc->draw_area->x1 + lv_area_get_width(dsc->draw_area) / 2 - label_size.x / 2;
label_area.x2 = label_area.x1 + label_size.x;
label_area.y2 = dsc->draw_area->y1 - 10;
label_area.y1 = label_area.y2 - label_size.y;
lv_draw_label_dsc_t label_draw_dsc;
lv_draw_label_dsc_init(&label_draw_dsc);
label_draw_dsc.color = lv_color_hex3(0x888);
lv_draw_label(dsc->draw_ctx, &label_draw_dsc, &label_area, buf, NULL);
}
}
}
#endif
def slider_event_cb(e):
code = e.get_code()
obj = e.get_target()
# Provide some extra space for the value
if code == lv.EVENT.REFR_EXT_DRAW_SIZE:
e.set_ext_draw_size(50)
elif code == lv.EVENT.DRAW_PART_END:
# print("DRAW_PART_END")
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
# print(dsc)
if dsc.part == lv.PART.INDICATOR:
label_text = "{:d} - {:d}".format(obj.get_left_value(),slider.get_value())
label_size = lv.point_t()
lv.txt_get_size(label_size, label_text, lv.font_default(), 0, 0, lv.COORD.MAX, 0)
# print(label_size.x,label_size.y)
label_area = lv.area_t()
label_area.x1 = dsc.draw_area.x1 + dsc.draw_area.get_width() // 2 - label_size.x // 2
label_area.x2 = label_area.x1 + label_size.x
label_area.y2 = dsc.draw_area.y1 - 10
label_area.y1 = label_area.y2 - label_size.y
label_draw_dsc = lv.draw_label_dsc_t()
label_draw_dsc.init()
dsc.draw_ctx.label(label_draw_dsc, label_area, label_text, None)
#
# Show the current value when the slider if pressed by extending the drawer
#
#
#Create a slider in the center of the display
slider = lv.slider(lv.scr_act())
slider.center()
slider.set_mode(lv.slider.MODE.RANGE)
slider.set_value(70, lv.ANIM.OFF)
slider.set_left_value(20, lv.ANIM.OFF)
slider.add_event_cb(slider_event_cb, lv.EVENT.ALL, None)
slider.refresh_ext_draw_size()
Span¶
Span with custom styles¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SPAN && LV_BUILD_EXAMPLES
/**
* Create span.
*/
void lv_example_span_1(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_border_width(&style, 1);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_ORANGE));
lv_style_set_pad_all(&style, 2);
lv_obj_t * spans = lv_spangroup_create(lv_scr_act());
lv_obj_set_width(spans, 300);
lv_obj_set_height(spans, 300);
lv_obj_center(spans);
lv_obj_add_style(spans, &style, 0);
lv_spangroup_set_align(spans, LV_TEXT_ALIGN_LEFT);
lv_spangroup_set_overflow(spans, LV_SPAN_OVERFLOW_CLIP);
lv_spangroup_set_indent(spans, 20);
lv_spangroup_set_mode(spans, LV_SPAN_MODE_BREAK);
lv_span_t * span = lv_spangroup_new_span(spans);
lv_span_set_text(span, "China is a beautiful country.");
lv_style_set_text_color(&span->style, lv_palette_main(LV_PALETTE_RED));
lv_style_set_text_decor(&span->style, LV_TEXT_DECOR_UNDERLINE);
lv_style_set_text_opa(&span->style, LV_OPA_50);
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "good good study, day day up.");
#if LV_FONT_MONTSERRAT_24
lv_style_set_text_font(&span->style, &lv_font_montserrat_24);
#endif
lv_style_set_text_color(&span->style, lv_palette_main(LV_PALETTE_GREEN));
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "LVGL is an open-source graphics library.");
lv_style_set_text_color(&span->style, lv_palette_main(LV_PALETTE_BLUE));
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "the boy no name.");
lv_style_set_text_color(&span->style, lv_palette_main(LV_PALETTE_GREEN));
#if LV_FONT_MONTSERRAT_20
lv_style_set_text_font(&span->style, &lv_font_montserrat_20);
#endif
lv_style_set_text_decor(&span->style, LV_TEXT_DECOR_UNDERLINE);
span = lv_spangroup_new_span(spans);
lv_span_set_text(span, "I have a dream that hope to come true.");
lv_style_set_text_decor(&span->style, LV_TEXT_DECOR_STRIKETHROUGH);
lv_spangroup_refr_mode(spans);
}
#endif
#
# Create span
#
style = lv.style_t()
style.init()
style.set_border_width(1)
style.set_border_color(lv.palette_main(lv.PALETTE.ORANGE))
style.set_pad_all(2)
spans = lv.spangroup(lv.scr_act())
spans.set_width(300)
spans.set_height(300)
spans.center()
spans.add_style(style, 0)
spans.set_align(lv.TEXT_ALIGN.LEFT)
spans.set_overflow(lv.SPAN_OVERFLOW.CLIP)
spans.set_indent(20)
spans.set_mode(lv.SPAN_MODE.BREAK)
span = spans.new_span()
span.set_text("china is a beautiful country.")
span.style.set_text_color(lv.palette_main(lv.PALETTE.RED))
span.style.set_text_decor(lv.TEXT_DECOR.STRIKETHROUGH | lv.TEXT_DECOR.UNDERLINE)
span.style.set_text_opa(lv.OPA._30)
span = spans.new_span()
span.set_text_static("good good study, day day up.")
#if LV_FONT_MONTSERRAT_24
# lv_style_set_text_font(&span->style, &lv_font_montserrat_24);
#endif
span.style.set_text_color(lv.palette_main(lv.PALETTE.GREEN))
span = spans.new_span()
span.set_text_static("LVGL is an open-source graphics library.")
span.style.set_text_color(lv.palette_main(lv.PALETTE.BLUE))
span = spans.new_span()
span.set_text_static("the boy no name.")
span.style.set_text_color(lv.palette_main(lv.PALETTE.GREEN))
#if LV_FONT_MONTSERRAT_20
# lv_style_set_text_font(&span->style, &lv_font_montserrat_20);
#endif
span.style.set_text_decor(lv.TEXT_DECOR.UNDERLINE)
span = spans.new_span()
span.set_text("I have a dream that hope to come true.")
spans.refr_mode()
# lv_span_del(spans, span);
# lv_obj_del(spans);
Spinbox¶
Simple Spinbox¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SPINBOX && LV_BUILD_EXAMPLES
static lv_obj_t * spinbox;
static void lv_spinbox_increment_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_SHORT_CLICKED || code == LV_EVENT_LONG_PRESSED_REPEAT) {
lv_spinbox_increment(spinbox);
}
}
static void lv_spinbox_decrement_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_SHORT_CLICKED || code == LV_EVENT_LONG_PRESSED_REPEAT) {
lv_spinbox_decrement(spinbox);
}
}
void lv_example_spinbox_1(void)
{
spinbox = lv_spinbox_create(lv_scr_act());
lv_spinbox_set_range(spinbox, -1000, 25000);
lv_spinbox_set_digit_format(spinbox, 5, 2);
lv_spinbox_step_prev(spinbox);
lv_obj_set_width(spinbox, 100);
lv_obj_center(spinbox);
lv_coord_t h = lv_obj_get_height(spinbox);
lv_obj_t * btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, h, h);
lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_RIGHT_MID, 5, 0);
lv_obj_set_style_bg_img_src(btn, LV_SYMBOL_PLUS, 0);
lv_obj_add_event_cb(btn, lv_spinbox_increment_event_cb, LV_EVENT_ALL, NULL);
btn = lv_btn_create(lv_scr_act());
lv_obj_set_size(btn, h, h);
lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_LEFT_MID, -5, 0);
lv_obj_set_style_bg_img_src(btn, LV_SYMBOL_MINUS, 0);
lv_obj_add_event_cb(btn, lv_spinbox_decrement_event_cb, LV_EVENT_ALL, NULL);
}
#endif
def increment_event_cb(e):
code = e.get_code()
if code == lv.EVENT.SHORT_CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
spinbox.increment()
def decrement_event_cb(e):
code = e.get_code()
if code == lv.EVENT.SHORT_CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
spinbox.decrement()
spinbox = lv.spinbox(lv.scr_act())
spinbox.set_range(-1000, 25000)
spinbox.set_digit_format(5, 2)
spinbox.step_prev()
spinbox.set_width(100)
spinbox.center()
h = spinbox.get_height()
btn = lv.btn(lv.scr_act())
btn.set_size(h, h)
btn.align_to(spinbox, lv.ALIGN.OUT_RIGHT_MID, 5, 0)
btn.set_style_bg_img_src(lv.SYMBOL.PLUS, 0)
btn.add_event_cb(increment_event_cb, lv.EVENT.ALL, None)
btn = lv.btn(lv.scr_act())
btn.set_size(h, h)
btn.align_to(spinbox, lv.ALIGN.OUT_LEFT_MID, -5, 0)
btn.set_style_bg_img_src(lv.SYMBOL.MINUS, 0)
btn.add_event_cb(decrement_event_cb, lv.EVENT.ALL, None)
Spinner¶
Simple spinner¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SPINNER && LV_BUILD_EXAMPLES
void lv_example_spinner_1(void)
{
/*Create a spinner*/
lv_obj_t * spinner = lv_spinner_create(lv_scr_act(), 1000, 60);
lv_obj_set_size(spinner, 100, 100);
lv_obj_center(spinner);
}
#endif
# Create a spinner
spinner = lv.spinner(lv.scr_act(), 1000, 60)
spinner.set_size(100, 100)
spinner.center()
Switch¶
Simple Switch¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_SWITCH && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
LV_LOG_USER("State: %s\n", lv_obj_has_state(obj, LV_STATE_CHECKED) ? "On" : "Off");
}
}
void lv_example_switch_1(void)
{
lv_obj_set_flex_flow(lv_scr_act(), LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(lv_scr_act(), LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
lv_obj_t * sw;
sw = lv_switch_create(lv_scr_act());
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_scr_act());
lv_obj_add_state(sw, LV_STATE_CHECKED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_scr_act());
lv_obj_add_state(sw, LV_STATE_DISABLED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_scr_act());
lv_obj_add_state(sw, LV_STATE_CHECKED | LV_STATE_DISABLED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.VALUE_CHANGED:
if obj.has_state(lv.STATE.CHECKED):
print("State: on")
else:
print("State: off")
lv.scr_act().set_flex_flow(lv.FLEX_FLOW.COLUMN)
lv.scr_act().set_flex_align(lv.FLEX_ALIGN.CENTER, lv.FLEX_ALIGN.CENTER, lv.FLEX_ALIGN.CENTER)
sw = lv.switch(lv.scr_act())
sw.add_event_cb(event_handler,lv.EVENT.ALL, None)
sw = lv.switch(lv.scr_act())
sw.add_state(lv.STATE.CHECKED)
sw.add_event_cb(event_handler, lv.EVENT.ALL, None)
sw = lv.switch(lv.scr_act())
sw.add_state(lv.STATE.DISABLED)
sw.add_event_cb(event_handler, lv.EVENT.ALL, None)
sw = lv.switch(lv.scr_act())
sw.add_state(lv.STATE.CHECKED | lv.STATE.DISABLED)
sw.add_event_cb(event_handler, lv.EVENT.ALL, None)
Table¶
Simple table¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TABLE && LV_BUILD_EXAMPLES
static void draw_part_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
/*If the cells are drawn...*/
if(dsc->part == LV_PART_ITEMS) {
uint32_t row = dsc->id / lv_table_get_col_cnt(obj);
uint32_t col = dsc->id - row * lv_table_get_col_cnt(obj);
/*Make the texts in the first cell center aligned*/
if(row == 0) {
dsc->label_dsc->align = LV_TEXT_ALIGN_CENTER;
dsc->rect_dsc->bg_color = lv_color_mix(lv_palette_main(LV_PALETTE_BLUE), dsc->rect_dsc->bg_color, LV_OPA_20);
dsc->rect_dsc->bg_opa = LV_OPA_COVER;
}
/*In the first column align the texts to the right*/
else if(col == 0) {
dsc->label_dsc->align = LV_TEXT_ALIGN_RIGHT;
}
/*MAke every 2nd row grayish*/
if((row != 0 && row % 2) == 0) {
dsc->rect_dsc->bg_color = lv_color_mix(lv_palette_main(LV_PALETTE_GREY), dsc->rect_dsc->bg_color, LV_OPA_10);
dsc->rect_dsc->bg_opa = LV_OPA_COVER;
}
}
}
void lv_example_table_1(void)
{
lv_obj_t * table = lv_table_create(lv_scr_act());
/*Fill the first column*/
lv_table_set_cell_value(table, 0, 0, "Name");
lv_table_set_cell_value(table, 1, 0, "Apple");
lv_table_set_cell_value(table, 2, 0, "Banana");
lv_table_set_cell_value(table, 3, 0, "Lemon");
lv_table_set_cell_value(table, 4, 0, "Grape");
lv_table_set_cell_value(table, 5, 0, "Melon");
lv_table_set_cell_value(table, 6, 0, "Peach");
lv_table_set_cell_value(table, 7, 0, "Nuts");
/*Fill the second column*/
lv_table_set_cell_value(table, 0, 1, "Price");
lv_table_set_cell_value(table, 1, 1, "$7");
lv_table_set_cell_value(table, 2, 1, "$4");
lv_table_set_cell_value(table, 3, 1, "$6");
lv_table_set_cell_value(table, 4, 1, "$2");
lv_table_set_cell_value(table, 5, 1, "$5");
lv_table_set_cell_value(table, 6, 1, "$1");
lv_table_set_cell_value(table, 7, 1, "$9");
/*Set a smaller height to the table. It'll make it scrollable*/
lv_obj_set_height(table, 200);
lv_obj_center(table);
/*Add an event callback to to apply some custom drawing*/
lv_obj_add_event_cb(table, draw_part_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
}
#endif
def draw_part_event_cb(e):
obj = e.get_target()
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
# If the cells are drawn../
if dsc.part == lv.PART.ITEMS:
row = dsc.id // obj.get_col_cnt()
col = dsc.id - row * obj.get_col_cnt()
# Make the texts in the first cell center aligned
if row == 0:
dsc.label_dsc.align = lv.TEXT_ALIGN.CENTER
dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.BLUE).color_mix(dsc.rect_dsc.bg_color, lv.OPA._20)
dsc.rect_dsc.bg_opa = lv.OPA.COVER
# In the first column align the texts to the right
elif col == 0:
dsc.label_dsc.flag = lv.TEXT_ALIGN.RIGHT
# Make every 2nd row grayish
if row != 0 and (row % 2) == 0:
dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.GREY).color_mix(dsc.rect_dsc.bg_color, lv.OPA._10)
dsc.rect_dsc.bg_opa = lv.OPA.COVER
table = lv.table(lv.scr_act())
# Fill the first column
table.set_cell_value(0, 0, "Name")
table.set_cell_value(1, 0, "Apple")
table.set_cell_value(2, 0, "Banana")
table.set_cell_value(3, 0, "Lemon")
table.set_cell_value(4, 0, "Grape")
table.set_cell_value(5, 0, "Melon")
table.set_cell_value(6, 0, "Peach")
table.set_cell_value(7, 0, "Nuts")
# Fill the second column
table.set_cell_value(0, 1, "Price")
table.set_cell_value(1, 1, "$7")
table.set_cell_value(2, 1, "$4")
table.set_cell_value(3, 1, "$6")
table.set_cell_value(4, 1, "$2")
table.set_cell_value(5, 1, "$5")
table.set_cell_value(6, 1, "$1")
table.set_cell_value(7, 1, "$9")
# Set a smaller height to the table. It'll make it scrollable
table.set_height(200)
table.center()
# Add an event callback to apply some custom drawing
table.add_event_cb(draw_part_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
Lightweighted list from table¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TABLE && LV_BUILD_EXAMPLES
#define ITEM_CNT 200
static void draw_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
/*If the cells are drawn...*/
if(dsc->part == LV_PART_ITEMS) {
bool chk = lv_table_has_cell_ctrl(obj, dsc->id, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.bg_color = chk ? lv_theme_get_color_primary(obj) : lv_palette_lighten(LV_PALETTE_GREY, 2);
rect_dsc.radius = LV_RADIUS_CIRCLE;
lv_area_t sw_area;
sw_area.x1 = dsc->draw_area->x2 - 50;
sw_area.x2 = sw_area.x1 + 40;
sw_area.y1 = dsc->draw_area->y1 + lv_area_get_height(dsc->draw_area) / 2 - 10;
sw_area.y2 = sw_area.y1 + 20;
lv_draw_rect(dsc->draw_ctx, &rect_dsc, &sw_area);
rect_dsc.bg_color = lv_color_white();
if(chk) {
sw_area.x2 -= 2;
sw_area.x1 = sw_area.x2 - 16;
}
else {
sw_area.x1 += 2;
sw_area.x2 = sw_area.x1 + 16;
}
sw_area.y1 += 2;
sw_area.y2 -= 2;
lv_draw_rect(dsc->draw_ctx, &rect_dsc, &sw_area);
}
}
static void change_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
uint16_t col;
uint16_t row;
lv_table_get_selected_cell(obj, &row, &col);
bool chk = lv_table_has_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
if(chk) lv_table_clear_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
else lv_table_add_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
}
/**
* A very light-weighted list created from table
*/
void lv_example_table_2(void)
{
/*Measure memory usage*/
lv_mem_monitor_t mon1;
lv_mem_monitor(&mon1);
uint32_t t = lv_tick_get();
lv_obj_t * table = lv_table_create(lv_scr_act());
/*Set a smaller height to the table. It'll make it scrollable*/
lv_obj_set_size(table, LV_SIZE_CONTENT, 200);
lv_table_set_col_width(table, 0, 150);
lv_table_set_row_cnt(table, ITEM_CNT); /*Not required but avoids a lot of memory reallocation lv_table_set_set_value*/
lv_table_set_col_cnt(table, 1);
/*Don't make the cell pressed, we will draw something different in the event*/
lv_obj_remove_style(table, NULL, LV_PART_ITEMS | LV_STATE_PRESSED);
uint32_t i;
for(i = 0; i < ITEM_CNT; i++) {
lv_table_set_cell_value_fmt(table, i, 0, "Item %"LV_PRIu32, i + 1);
}
lv_obj_align(table, LV_ALIGN_CENTER, 0, -20);
/*Add an event callback to to apply some custom drawing*/
lv_obj_add_event_cb(table, draw_event_cb, LV_EVENT_DRAW_PART_END, NULL);
lv_obj_add_event_cb(table, change_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_mem_monitor_t mon2;
lv_mem_monitor(&mon2);
uint32_t mem_used = mon1.free_size - mon2.free_size;
uint32_t elaps = lv_tick_elaps(t);
lv_obj_t * label = lv_label_create(lv_scr_act());
lv_label_set_text_fmt(label, "%"LV_PRIu32" items were created in %"LV_PRIu32" ms\n"
"using %"LV_PRIu32" bytes of memory",
ITEM_CNT, elaps, mem_used);
lv_obj_align(label, LV_ALIGN_BOTTOM_MID, 0, -10);
}
#endif
from utime import ticks_ms
import gc
ITEM_CNT = 200
def draw_event_cb(e):
obj = e.get_target()
dsc = lv.obj_draw_part_dsc_t.__cast__(e.get_param())
# If the cells are drawn...
if dsc.part == lv.PART.ITEMS:
chk = obj.has_cell_ctrl(dsc.id, 0, lv.table.CELL_CTRL.CUSTOM_1)
rect_dsc = lv.draw_rect_dsc_t()
rect_dsc.init()
if chk:
rect_dsc.bg_color = lv.theme_get_color_primary(obj)
else:
rect_dsc.bg_color = lv.palette_lighten(lv.PALETTE.GREY, 2)
rect_dsc.radius = lv.RADIUS.CIRCLE
sw_area = lv.area_t()
sw_area.x1 = dsc.draw_area.x2 - 50
sw_area.x2 = sw_area.x1 + 40
sw_area.y1 = dsc.draw_area.y1 + dsc.draw_area.get_height() // 2 - 10
sw_area.y2 = sw_area.y1 + 20
dsc.draw_ctx.rect(rect_dsc, sw_area)
rect_dsc.bg_color = lv.color_white()
if chk:
sw_area.x2 -= 2
sw_area.x1 = sw_area.x2 - 16
else:
sw_area.x1 += 2
sw_area.x2 = sw_area.x1 + 16
sw_area.y1 += 2
sw_area.y2 -= 2
dsc.draw_ctx.rect(rect_dsc, sw_area)
def change_event_cb(e):
obj = e.get_target()
row = lv.C_Pointer()
col = lv.C_Pointer()
table.get_selected_cell(row, col)
# print("row: ",row.uint_val)
chk = table.has_cell_ctrl(row.uint_val, 0, lv.table.CELL_CTRL.CUSTOM_1)
if chk:
table.clear_cell_ctrl(row.uint_val, 0, lv.table.CELL_CTRL.CUSTOM_1)
else:
table.add_cell_ctrl(row.uint_val, 0, lv.table.CELL_CTRL.CUSTOM_1)
#
# A very light-weighted list created from table
#
# Measure memory usage
gc.enable()
gc.collect()
mem_free = gc.mem_free()
print("mem_free: ", mem_free)
t = ticks_ms()
print("ticks: ", t)
table = lv.table(lv.scr_act())
# Set a smaller height to the table. It'll make it scrollable
table.set_size(150, 200)
table.set_col_width(0, 150)
table.set_row_cnt(ITEM_CNT) # Not required but avoids a lot of memory reallocation lv_table_set_set_value
table.set_col_cnt(1)
# Don't make the cell pressed, we will draw something different in the event
table.remove_style(None, lv.PART.ITEMS | lv.STATE.PRESSED)
for i in range(ITEM_CNT):
table.set_cell_value(i, 0, "Item " + str(i+1))
table.align(lv.ALIGN.CENTER, 0, -20)
# Add an event callback to apply some custom drawing
table.add_event_cb(draw_event_cb, lv.EVENT.DRAW_PART_END, None)
table.add_event_cb(change_event_cb, lv.EVENT.VALUE_CHANGED, None)
gc.collect()
mem_used = mem_free - gc.mem_free()
elaps = ticks_ms()-t
label = lv.label(lv.scr_act())
label.set_text(str(ITEM_CNT) + " items were created in " + str(elaps) + " ms\n using " + str(mem_used) + " bytes of memory")
#label.set_text(str(ITEM_CNT) + " items were created in " + str(elaps) + " ms")
label.align(lv.ALIGN.BOTTOM_MID, 0, -10)
Tabview¶
Simple Tabview¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TABVIEW && LV_BUILD_EXAMPLES
void lv_example_tabview_1(void)
{
/*Create a Tab view object*/
lv_obj_t * tabview;
tabview = lv_tabview_create(lv_scr_act(), LV_DIR_TOP, 50);
/*Add 3 tabs (the tabs are page (lv_page) and can be scrolled*/
lv_obj_t * tab1 = lv_tabview_add_tab(tabview, "Tab 1");
lv_obj_t * tab2 = lv_tabview_add_tab(tabview, "Tab 2");
lv_obj_t * tab3 = lv_tabview_add_tab(tabview, "Tab 3");
/*Add content to the tabs*/
lv_obj_t * label = lv_label_create(tab1);
lv_label_set_text(label, "This the first tab\n\n"
"If the content\n"
"of a tab\n"
"becomes too\n"
"longer\n"
"than the\n"
"container\n"
"then it\n"
"automatically\n"
"becomes\n"
"scrollable.\n"
"\n"
"\n"
"\n"
"Can you see it?");
label = lv_label_create(tab2);
lv_label_set_text(label, "Second tab");
label = lv_label_create(tab3);
lv_label_set_text(label, "Third tab");
lv_obj_scroll_to_view_recursive(label, LV_ANIM_ON);
}
#endif
# Create a Tab view object
tabview = lv.tabview(lv.scr_act(), lv.DIR.TOP, 50)
# Add 3 tabs (the tabs are page (lv_page) and can be scrolled
tab1 = tabview.add_tab("Tab 1")
tab2 = tabview.add_tab("Tab 2")
tab3 = tabview.add_tab("Tab 3")
# Add content to the tabs
label = lv.label(tab1)
label.set_text("""This the first tab
If the content
of a tab
becomes too
longer
than the
container
then it
automatically
becomes
scrollable.
Can you see it?""")
label = lv.label(tab2)
label.set_text("Second tab")
label = lv.label(tab3)
label.set_text("Third tab");
label.scroll_to_view_recursive(lv.ANIM.ON)
Tabs on the left, styling and no scrolling¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TABVIEW && LV_BUILD_EXAMPLES
void lv_example_tabview_2(void)
{
/*Create a Tab view object*/
lv_obj_t * tabview;
tabview = lv_tabview_create(lv_scr_act(), LV_DIR_LEFT, 80);
lv_obj_set_style_bg_color(tabview, lv_palette_lighten(LV_PALETTE_RED, 2), 0);
lv_obj_t * tab_btns = lv_tabview_get_tab_btns(tabview);
lv_obj_set_style_bg_color(tab_btns, lv_palette_darken(LV_PALETTE_GREY, 3), 0);
lv_obj_set_style_text_color(tab_btns, lv_palette_lighten(LV_PALETTE_GREY, 5), 0);
lv_obj_set_style_border_side(tab_btns, LV_BORDER_SIDE_RIGHT, LV_PART_ITEMS | LV_STATE_CHECKED);
/*Add 3 tabs (the tabs are page (lv_page) and can be scrolled*/
lv_obj_t * tab1 = lv_tabview_add_tab(tabview, "Tab 1");
lv_obj_t * tab2 = lv_tabview_add_tab(tabview, "Tab 2");
lv_obj_t * tab3 = lv_tabview_add_tab(tabview, "Tab 3");
lv_obj_t * tab4 = lv_tabview_add_tab(tabview, "Tab 4");
lv_obj_t * tab5 = lv_tabview_add_tab(tabview, "Tab 5");
lv_obj_set_style_bg_color(tab2, lv_palette_lighten(LV_PALETTE_AMBER, 3), 0);
lv_obj_set_style_bg_opa(tab2, LV_OPA_COVER, 0);
/*Add content to the tabs*/
lv_obj_t * label = lv_label_create(tab1);
lv_label_set_text(label, "First tab");
label = lv_label_create(tab2);
lv_label_set_text(label, "Second tab");
label = lv_label_create(tab3);
lv_label_set_text(label, "Third tab");
label = lv_label_create(tab4);
lv_label_set_text(label, "Forth tab");
label = lv_label_create(tab5);
lv_label_set_text(label, "Fifth tab");
lv_obj_clear_flag(lv_tabview_get_content(tabview), LV_OBJ_FLAG_SCROLLABLE);
}
#endif
# Create a Tab view object
tabview = lv.tabview(lv.scr_act(), lv.DIR.LEFT, 80)
tabview.set_style_bg_color(lv.palette_lighten(lv.PALETTE.RED, 2), 0)
tab_btns = tabview.get_tab_btns()
tab_btns.set_style_bg_color(lv.palette_darken(lv.PALETTE.GREY, 3), 0)
tab_btns.set_style_text_color(lv.palette_lighten(lv.PALETTE.GREY, 5), 0)
tab_btns.set_style_border_side(lv.BORDER_SIDE.RIGHT, lv.PART.ITEMS | lv.STATE.CHECKED)
# Add 3 tabs (the tabs are page (lv_page) and can be scrolled
tab1 = tabview.add_tab("Tab 1")
tab2 = tabview.add_tab("Tab 2")
tab3 = tabview.add_tab("Tab 3")
tab4 = tabview.add_tab("Tab 4")
tab5 = tabview.add_tab("Tab 5")
tab2.set_style_bg_color(lv.palette_lighten(lv.PALETTE.AMBER, 3), 0)
tab2.set_style_bg_opa(lv.OPA.COVER, 0)
# Add content to the tabs
label = lv.label(tab1)
label.set_text("First tab")
label = lv.label(tab2)
label.set_text("Second tab")
label = lv.label(tab3)
label.set_text("Third tab")
label = lv.label(tab4)
label.set_text("Forth tab")
label = lv.label(tab5)
label.set_text("Fifth tab")
tabview.get_content().clear_flag(lv.obj.FLAG.SCROLLABLE)
Textarea¶
Simple Text area¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_BUILD_EXAMPLES
static void textarea_event_handler(lv_event_t * e)
{
lv_obj_t * ta = lv_event_get_target(e);
LV_LOG_USER("Enter was pressed. The current text is: %s", lv_textarea_get_text(ta));
}
static void btnm_event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_obj_t * ta = lv_event_get_user_data(e);
const char * txt = lv_btnmatrix_get_btn_text(obj, lv_btnmatrix_get_selected_btn(obj));
if(strcmp(txt, LV_SYMBOL_BACKSPACE) == 0) lv_textarea_del_char(ta);
else if(strcmp(txt, LV_SYMBOL_NEW_LINE) == 0) lv_event_send(ta, LV_EVENT_READY, NULL);
else lv_textarea_add_text(ta, txt);
}
void lv_example_textarea_1(void)
{
lv_obj_t * ta = lv_textarea_create(lv_scr_act());
lv_textarea_set_one_line(ta, true);
lv_obj_align(ta, LV_ALIGN_TOP_MID, 0, 10);
lv_obj_add_event_cb(ta, textarea_event_handler, LV_EVENT_READY, ta);
lv_obj_add_state(ta, LV_STATE_FOCUSED); /*To be sure the cursor is visible*/
static const char * btnm_map[] = {"1", "2", "3", "\n",
"4", "5", "6", "\n",
"7", "8", "9", "\n",
LV_SYMBOL_BACKSPACE, "0", LV_SYMBOL_NEW_LINE, ""
};
lv_obj_t * btnm = lv_btnmatrix_create(lv_scr_act());
lv_obj_set_size(btnm, 200, 150);
lv_obj_align(btnm, LV_ALIGN_BOTTOM_MID, 0, -10);
lv_obj_add_event_cb(btnm, btnm_event_handler, LV_EVENT_VALUE_CHANGED, ta);
lv_obj_clear_flag(btnm, LV_OBJ_FLAG_CLICK_FOCUSABLE); /*To keep the text area focused on button clicks*/
lv_btnmatrix_set_map(btnm, btnm_map);
}
#endif
def textarea_event_handler(e, ta):
print("Enter was pressed. The current text is: " + ta.get_text())
def btnm_event_handler(e, ta):
obj = e.get_target()
txt = obj.get_btn_text(obj.get_selected_btn())
if txt == lv.SYMBOL.BACKSPACE:
ta.del_char()
elif txt == lv.SYMBOL.NEW_LINE:
lv.event_send(ta, lv.EVENT.READY, None)
elif txt:
ta.add_text(txt)
ta = lv.textarea(lv.scr_act())
ta.set_one_line(True)
ta.align(lv.ALIGN.TOP_MID, 0, 10)
ta.add_event_cb(lambda e: textarea_event_handler(e, ta), lv.EVENT.READY, None)
ta.add_state(lv.STATE.FOCUSED) # To be sure the cursor is visible
btnm_map = ["1", "2", "3", "\n",
"4", "5", "6", "\n",
"7", "8", "9", "\n",
lv.SYMBOL.BACKSPACE, "0", lv.SYMBOL.NEW_LINE, ""]
btnm = lv.btnmatrix(lv.scr_act())
btnm.set_size(200, 150)
btnm.align(lv.ALIGN.BOTTOM_MID, 0, -10)
btnm.add_event_cb(lambda e: btnm_event_handler(e, ta), lv.EVENT.VALUE_CHANGED, None)
btnm.clear_flag(lv.obj.FLAG.CLICK_FOCUSABLE) # To keep the text area focused on button clicks
btnm.set_map(btnm_map)
Text area with password field¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e);
static lv_obj_t * kb;
void lv_example_textarea_2(void)
{
/*Create the password box*/
lv_obj_t * pwd_ta = lv_textarea_create(lv_scr_act());
lv_textarea_set_text(pwd_ta, "");
lv_textarea_set_password_mode(pwd_ta, true);
lv_textarea_set_one_line(pwd_ta, true);
lv_obj_set_width(pwd_ta, lv_pct(40));
lv_obj_set_pos(pwd_ta, 5, 20);
lv_obj_add_event_cb(pwd_ta, ta_event_cb, LV_EVENT_ALL, NULL);
/*Create a label and position it above the text box*/
lv_obj_t * pwd_label = lv_label_create(lv_scr_act());
lv_label_set_text(pwd_label, "Password:");
lv_obj_align_to(pwd_label, pwd_ta, LV_ALIGN_OUT_TOP_LEFT, 0, 0);
/*Create the one-line mode text area*/
lv_obj_t * text_ta = lv_textarea_create(lv_scr_act());
lv_textarea_set_one_line(text_ta, true);
lv_textarea_set_password_mode(text_ta, false);
lv_obj_set_width(text_ta, lv_pct(40));
lv_obj_add_event_cb(text_ta, ta_event_cb, LV_EVENT_ALL, NULL);
lv_obj_align(text_ta, LV_ALIGN_TOP_RIGHT, -5, 20);
/*Create a label and position it above the text box*/
lv_obj_t * oneline_label = lv_label_create(lv_scr_act());
lv_label_set_text(oneline_label, "Text:");
lv_obj_align_to(oneline_label, text_ta, LV_ALIGN_OUT_TOP_LEFT, 0, 0);
/*Create a keyboard*/
kb = lv_keyboard_create(lv_scr_act());
lv_obj_set_size(kb, LV_HOR_RES, LV_VER_RES / 2);
lv_keyboard_set_textarea(kb, pwd_ta); /*Focus it on one of the text areas to start*/
}
static void ta_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * ta = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED || code == LV_EVENT_FOCUSED) {
/*Focus on the clicked text area*/
if(kb != NULL) lv_keyboard_set_textarea(kb, ta);
}
else if(code == LV_EVENT_READY) {
LV_LOG_USER("Ready, current text: %s", lv_textarea_get_text(ta));
}
}
#endif
def ta_event_cb(e):
code = e.get_code()
ta = e.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.FOCUSED:
# Focus on the clicked text area
if kb != None:
kb.set_textarea(ta)
elif code == lv.EVENT.READY:
print("Ready, current text: " + ta.get_text())
# Create the password box
LV_HOR_RES = lv.scr_act().get_disp().driver.hor_res
LV_VER_RES = lv.scr_act().get_disp().driver.ver_res
pwd_ta = lv.textarea(lv.scr_act())
pwd_ta.set_text("")
pwd_ta.set_password_mode(True)
pwd_ta.set_one_line(True)
pwd_ta.set_width(LV_HOR_RES // 2 - 20)
pwd_ta.set_pos(5, 20)
pwd_ta.add_event_cb(ta_event_cb, lv.EVENT.ALL, None)
# Create a label and position it above the text box
pwd_label = lv.label(lv.scr_act())
pwd_label.set_text("Password:")
pwd_label.align_to(pwd_ta, lv.ALIGN.OUT_TOP_LEFT, 0, 0)
# Create the one-line mode text area
text_ta = lv.textarea(lv.scr_act())
text_ta.set_width(LV_HOR_RES // 2 - 20)
text_ta.set_one_line(True)
text_ta.add_event_cb(ta_event_cb, lv.EVENT.ALL, None)
text_ta.set_password_mode(False)
text_ta.align(lv.ALIGN.TOP_RIGHT, -5, 20)
# Create a label and position it above the text box
oneline_label = lv.label(lv.scr_act())
oneline_label.set_text("Text:")
oneline_label.align_to(text_ta, lv.ALIGN.OUT_TOP_LEFT, 0, 0)
# Create a keyboard
kb = lv.keyboard(lv.scr_act())
kb.set_size(LV_HOR_RES, LV_VER_RES // 2)
kb.set_textarea(pwd_ta) # Focus it on one of the text areas to start
Text auto-formatting¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e);
static lv_obj_t * kb;
/**
* Automatically format text like a clock. E.g. "12:34"
* Add the ':' automatically.
*/
void lv_example_textarea_3(void)
{
/*Create the text area*/
lv_obj_t * ta = lv_textarea_create(lv_scr_act());
lv_obj_add_event_cb(ta, ta_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_textarea_set_accepted_chars(ta, "0123456789:");
lv_textarea_set_max_length(ta, 5);
lv_textarea_set_one_line(ta, true);
lv_textarea_set_text(ta, "");
/*Create a keyboard*/
kb = lv_keyboard_create(lv_scr_act());
lv_obj_set_size(kb, LV_HOR_RES, LV_VER_RES / 2);
lv_keyboard_set_mode(kb, LV_KEYBOARD_MODE_NUMBER);
lv_keyboard_set_textarea(kb, ta);
}
static void ta_event_cb(lv_event_t * e)
{
lv_obj_t * ta = lv_event_get_target(e);
const char * txt = lv_textarea_get_text(ta);
if(txt[0] >= '0' && txt[0] <= '9' &&
txt[1] >= '0' && txt[1] <= '9' &&
txt[2] != ':') {
lv_textarea_set_cursor_pos(ta, 2);
lv_textarea_add_char(ta, ':');
}
}
#endif
def ta_event_cb(e):
ta = e.get_target()
txt = ta.get_text()
# print(txt)
pos = ta.get_cursor_pos()
# print("cursor pos: ",pos)
# find position of ":" in text
colon_pos= txt.find(":")
# if there are more than 2 digits before the colon, remove the last one entered
if colon_pos == 3:
ta.del_char()
if colon_pos != -1:
# if there are more than 3 digits after the ":" remove the last one entered
rest = txt[colon_pos:]
if len(rest) > 3:
ta.del_char()
if len(txt) < 2:
return
if ":" in txt:
return
if txt[0] >= '0' and txt[0] <= '9' and \
txt[1] >= '0' and txt[1] <= '9':
if len(txt) == 2 or txt[2] != ':' :
ta.set_cursor_pos(2)
ta.add_char(ord(':'))
#
# Automatically format text like a clock. E.g. "12:34"
# Add the ':' automatically
#
# Create the text area
LV_HOR_RES = lv.scr_act().get_disp().driver.hor_res
LV_VER_RES = lv.scr_act().get_disp().driver.ver_res
ta = lv.textarea(lv.scr_act())
ta.add_event_cb(ta_event_cb, lv.EVENT.VALUE_CHANGED, None)
ta.set_accepted_chars("0123456789:")
ta.set_max_length(5)
ta.set_one_line(True)
ta.set_text("")
ta.add_state(lv.STATE.FOCUSED)
# Create a keyboard
kb = lv.keyboard(lv.scr_act())
kb.set_size(LV_HOR_RES, LV_VER_RES // 2)
kb.set_mode(lv.keyboard.MODE.NUMBER)
kb.set_textarea(ta)
Tabview¶
Tileview with content¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_TILEVIEW && LV_BUILD_EXAMPLES
/**
* Create a 2x2 tile view and allow scrolling only in an "L" shape.
* Demonstrate scroll chaining with a long list that
* scrolls the tile view when it can't be scrolled further.
*/
void lv_example_tileview_1(void)
{
lv_obj_t * tv = lv_tileview_create(lv_scr_act());
/*Tile1: just a label*/
lv_obj_t * tile1 = lv_tileview_add_tile(tv, 0, 0, LV_DIR_BOTTOM);
lv_obj_t * label = lv_label_create(tile1);
lv_label_set_text(label, "Scroll down");
lv_obj_center(label);
/*Tile2: a button*/
lv_obj_t * tile2 = lv_tileview_add_tile(tv, 0, 1, LV_DIR_TOP | LV_DIR_RIGHT);
lv_obj_t * btn = lv_btn_create(tile2);
label = lv_label_create(btn);
lv_label_set_text(label, "Scroll up or right");
lv_obj_set_size(btn, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_center(btn);
/*Tile3: a list*/
lv_obj_t * tile3 = lv_tileview_add_tile(tv, 1, 1, LV_DIR_LEFT);
lv_obj_t * list = lv_list_create(tile3);
lv_obj_set_size(list, LV_PCT(100), LV_PCT(100));
lv_list_add_btn(list, NULL, "One");
lv_list_add_btn(list, NULL, "Two");
lv_list_add_btn(list, NULL, "Three");
lv_list_add_btn(list, NULL, "Four");
lv_list_add_btn(list, NULL, "Five");
lv_list_add_btn(list, NULL, "Six");
lv_list_add_btn(list, NULL, "Seven");
lv_list_add_btn(list, NULL, "Eight");
lv_list_add_btn(list, NULL, "Nine");
lv_list_add_btn(list, NULL, "Ten");
}
#endif
#
# Create a 2x2 tile view and allow scrolling only in an "L" shape.
# Demonstrate scroll chaining with a long list that
# scrolls the tile view when it can't be scrolled further.
#
tv = lv.tileview(lv.scr_act())
# Tile1: just a label
tile1 = tv.add_tile(0, 0, lv.DIR.BOTTOM)
label = lv.label(tile1)
label.set_text("Scroll down")
label.center()
# Tile2: a button
tile2 = tv.add_tile(0, 1, lv.DIR.TOP | lv.DIR.RIGHT)
btn = lv.btn(tile2)
label = lv.label(btn)
label.set_text("Scroll up or right")
btn.set_size(lv.SIZE.CONTENT, lv.SIZE.CONTENT)
btn.center()
# Tile3: a list
tile3 = tv.add_tile(1, 1, lv.DIR.LEFT)
list = lv.list(tile3)
list.set_size(lv.pct(100), lv.pct(100))
list.add_btn(None, "One")
list.add_btn(None, "Two")
list.add_btn(None, "Three")
list.add_btn(None, "Four")
list.add_btn(None, "Five")
list.add_btn(None, "Six")
list.add_btn(None, "Seven")
list.add_btn(None, "Eight")
list.add_btn(None, "Nine")
list.add_btn(None, "Ten")
Window¶
Simple window¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_WIN && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
LV_LOG_USER("Button %d clicked", (int)lv_obj_get_index(obj));
}
void lv_example_win_1(void)
{
lv_obj_t * win = lv_win_create(lv_scr_act(), 40);
lv_obj_t * btn;
btn = lv_win_add_btn(win, LV_SYMBOL_LEFT, 40);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_win_add_title(win, "A title");
btn = lv_win_add_btn(win, LV_SYMBOL_RIGHT, 40);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_win_add_btn(win, LV_SYMBOL_CLOSE, 60);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t * cont = lv_win_get_content(win); /*Content can be added here*/
lv_obj_t * label = lv_label_create(cont);
lv_label_set_text(label, "This is\n"
"a pretty\n"
"long text\n"
"to see how\n"
"the window\n"
"becomes\n"
"scrollable.\n"
"\n"
"\n"
"Some more\n"
"text to be\n"
"sure it\n"
"overflows. :)");
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.CLICKED:
print("Button {:d} clicked".format(obj.get_child_id()))
win = lv.win(lv.scr_act(), 60)
btn1 = win.add_btn(lv.SYMBOL.LEFT, 40)
btn1.add_event_cb(event_handler, lv.EVENT.ALL, None)
win.add_title("A title")
btn2=win.add_btn(lv.SYMBOL.RIGHT, 40)
btn2.add_event_cb(event_handler, lv.EVENT.ALL, None)
btn3 = win.add_btn(lv.SYMBOL.CLOSE, 60)
btn3.add_event_cb(event_handler, lv.EVENT.ALL, None)
cont = win.get_content() # Content can be added here
label = lv.label(cont)
label.set_text("""This is
a pretty
long text
to see how
the window
becomes
scrollable.
We need
quite some text
and we will
even put
some more
text to be
sure it
overflows.
""")