Examples
Get Started
A very simple hello world label
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
/**
* Basic example to create a "Hello world" label
*/
void lv_example_get_started_1(void)
{
/*Change the active screen's background color*/
lv_obj_set_style_bg_color(lv_screen_active(), lv_color_hex(0x003a57), LV_PART_MAIN);
/*Create a white label, set its text and align it to the center*/
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Hello world");
lv_obj_set_style_text_color(lv_screen_active(), lv_color_hex(0xffffff), LV_PART_MAIN);
lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);
}
#endif
Create a slider and write its value on a label
C code
View on 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_4(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_screen_active());
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_screen_active());
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
Styles
Size styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label, "Hello");
}
#endif
Background styles
C code
View on 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[0].opa = LV_OPA_COVER;
grad.stops[1].color = lv_palette_main(LV_PALETTE_BLUE);
grad.stops[1].opa = LV_OPA_COVER;
/*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_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Border styles
C code
View on 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_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Outline styles
C code
View on 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_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Shadow styles
C code
View on 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));
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Image styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_image_recolor(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_image_recolor_opa(&style, LV_OPA_50);
lv_style_set_transform_rotation(&style, 300);
/*Create an object with the new style*/
lv_obj_t * obj = lv_image_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
LV_IMAGE_DECLARE(img_cogwheel_argb);
lv_image_set_src(obj, &img_cogwheel_argb);
lv_obj_center(obj);
}
#endif
Arc styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_ARC
/**
* Using the Arc style properties
*/
void lv_example_style_7(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_arc_color(&style, lv_palette_main(LV_PALETTE_RED));
lv_style_set_arc_width(&style, 4);
/*Create an object with the new style*/
lv_obj_t * obj = lv_arc_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Text styles
C code
View on 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_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_label_set_text(obj, "Text of\n"
"a label");
lv_obj_center(obj);
}
#endif
Line styles
C code
View on 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_screen_active());
lv_obj_add_style(obj, &style, 0);
static lv_point_precise_t p[] = {{10, 30}, {30, 50}, {100, 0}};
lv_line_set_points(obj, p, 3);
lv_obj_center(obj);
}
#endif
Transition
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_screen_active());
lv_obj_add_style(obj, &style_def, 0);
lv_obj_add_style(obj, &style_pr, LV_STATE_PRESSED);
lv_obj_center(obj);
}
#endif
Using multiple styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_offset_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_screen_active());
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_screen_active());
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
Local styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_screen_active());
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
Add styles to parts and states
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* 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_screen_active());
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
Extending the current theme
C code
View on GitHub#include "../../src/themes/lv_theme_private.h"
#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
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_button_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_display_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_display_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_button_create(lv_screen_active());
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_button_create(lv_screen_active());
lv_obj_align(btn, LV_ALIGN_BOTTOM_MID, 0, -20);
label = lv_label_create(btn);
lv_label_set_text(label, "New theme");
}
#endif
Opacity and Transformations
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_BUTTON && LV_USE_LABEL
/**
* Opacity and Transformations
*/
void lv_example_style_15(void)
{
lv_obj_t * btn;
lv_obj_t * label;
/*Normal button*/
btn = lv_button_create(lv_screen_active());
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_button_create(lv_screen_active());
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_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 40);
lv_obj_set_style_transform_rotation(btn, 150, 0); /*15 deg*/
lv_obj_set_style_transform_scale(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
Metallic knob with conic gradient
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
#if LV_USE_DRAW_SW_COMPLEX_GRADIENTS
/**
* Simulate metallic knob using conical gradient
* For best effect set LV_GRADIENT_MAX_STOPS to 8 or at least 3
*/
void lv_example_style_16(void)
{
#if LV_GRADIENT_MAX_STOPS >= 8
static const lv_color_t grad_colors[8] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0xff, 0xff, 0xff),
LV_COLOR_MAKE(0xfa, 0xfa, 0xfa),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
LV_COLOR_MAKE(0x48, 0x48, 0x48),
LV_COLOR_MAKE(0x4b, 0x4b, 0x4b),
LV_COLOR_MAKE(0x70, 0x70, 0x70),
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
};
#elif LV_GRADIENT_MAX_STOPS >= 3
static const lv_color_t grad_colors[3] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0xff, 0xff, 0xff),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
};
#else
static const lv_color_t grad_colors[2] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
};
#endif
/*Create a style with gradient background and shadow*/
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 500);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_shadow_color(&style, lv_color_black());
lv_style_set_shadow_width(&style, 50);
lv_style_set_shadow_offset_x(&style, 20);
lv_style_set_shadow_offset_y(&style, 20);
lv_style_set_shadow_opa(&style, LV_OPA_50);
/*First define a color gradient. In this example we use a gray color map with random values.*/
static lv_grad_dsc_t grad;
lv_gradient_init_stops(&grad, grad_colors, NULL, NULL, sizeof(grad_colors) / sizeof(lv_color_t));
/*Make a conical gradient with the center in the middle of the object*/
#if LV_GRADIENT_MAX_STOPS >= 8
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 0, 120, LV_GRAD_EXTEND_REFLECT);
#elif LV_GRADIENT_MAX_STOPS >= 3
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 45, 125, LV_GRAD_EXTEND_REFLECT);
#else
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 45, 110, LV_GRAD_EXTEND_REFLECT);
#endif
/*Set gradient as background*/
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_set_size(obj, 200, 200);
lv_obj_center(obj);
}
#else
void lv_example_style_16(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_obj_set_width(label, LV_PCT(80));
lv_label_set_text(label, "LV_USE_DRAW_SW_COMPLEX_GRADIENTS is not enabled");
lv_label_set_long_mode(label, LV_LABEL_LONG_SCROLL_CIRCULAR);
lv_obj_center(label);
}
#endif /*LV_USE_DRAW_SW_COMPLEX_GRADIENTS*/
#endif /*LV_BUILD_EXAMPLES*/
Radial gradient as background
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
#if LV_USE_DRAW_SW_COMPLEX_GRADIENTS
/**
* Using radial gradient as background
*/
void lv_example_style_17(void)
{
static const lv_color_t grad_colors[2] = {
LV_COLOR_MAKE(0x9B, 0x18, 0x42),
LV_COLOR_MAKE(0x00, 0x00, 0x00),
};
int32_t width = lv_display_get_horizontal_resolution(NULL);
int32_t height = lv_display_get_vertical_resolution(NULL);
static lv_style_t style;
lv_style_init(&style);
/*First define a color gradient. In this example we use a purple to black color map.*/
static lv_grad_dsc_t grad;
lv_gradient_init_stops(&grad, grad_colors, NULL, NULL, sizeof(grad_colors) / sizeof(lv_color_t));
/*Make a radial gradient with the center in the middle of the object, extending to the farthest corner*/
lv_grad_radial_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, LV_GRAD_RIGHT, LV_GRAD_BOTTOM, LV_GRAD_EXTEND_PAD);
/*Set gradient as background*/
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_set_size(obj, width, height);
lv_obj_center(obj);
}
#else
void lv_example_style_17(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_obj_set_width(label, LV_PCT(80));
lv_label_set_text(label, "LV_USE_DRAW_SW_COMPLEX_GRADIENTS is not enabled");
lv_label_set_long_mode(label, LV_LABEL_LONG_SCROLL_CIRCULAR);
lv_obj_center(label);
}
#endif /*LV_USE_DRAW_SW_COMPLEX_GRADIENTS*/
#endif /*LV_BUILD_EXAMPLES*/
Animations
Start animation on an event
C code
View on 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_duration(&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_duration(&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_screen_active());
lv_label_set_text(label, "Hello animations!");
lv_obj_set_pos(label, 100, 10);
lv_obj_t * sw = lv_switch_create(lv_screen_active());
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
Playback animation
C code
View on 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_screen_active());
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_duration(&a, 1000);
lv_anim_set_playback_delay(&a, 100);
lv_anim_set_playback_duration(&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
Cubic Bezier animation
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SLIDER && LV_USE_CHART && LV_USE_BUTTON && LV_USE_GRID
/**
* the example show the use of cubic-bezier3 in animation.
* the control point P1,P2 of cubic-bezier3 can be adjusted by slider.
* and the chart shows the cubic-bezier3 in real time. you can click
* run button see animation in current point of cubic-bezier3.
*/
#define CHART_POINTS_NUM 256
struct {
lv_obj_t * anim_obj;
lv_obj_t * chart;
lv_chart_series_t * ser1;
lv_obj_t * p1_slider;
lv_obj_t * p1_label;
lv_obj_t * p2_slider;
lv_obj_t * p2_label;
lv_obj_t * run_btn;
uint16_t p1;
uint16_t p2;
lv_anim_t a;
} ginfo;
static int32_t anim_path_bezier3_cb(const lv_anim_t * a);
static void refer_chart_cubic_bezier(void);
static void run_button_event_handler(lv_event_t * e);
static void slider_event_cb(lv_event_t * e);
static void page_obj_init(lv_obj_t * par);
static void anim_x_cb(void * var, int32_t v);
/**
* create an animation
*/
void lv_example_anim_3(void)
{
static int32_t col_dsc[] = {LV_GRID_FR(1), 200, LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {30, 10, 10, LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_style_pad_all(cont, 2, LV_PART_MAIN);
lv_obj_set_style_pad_column(cont, 10, LV_PART_MAIN);
lv_obj_set_style_pad_row(cont, 10, LV_PART_MAIN);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 320, 240);
lv_obj_center(cont);
page_obj_init(cont);
lv_anim_init(&ginfo.a);
lv_anim_set_var(&ginfo.a, ginfo.anim_obj);
int32_t end = lv_obj_get_style_width(cont, LV_PART_MAIN) -
lv_obj_get_style_width(ginfo.anim_obj, LV_PART_MAIN) - 10;
lv_anim_set_values(&ginfo.a, 5, end);
lv_anim_set_duration(&ginfo.a, 2000);
lv_anim_set_exec_cb(&ginfo.a, anim_x_cb);
lv_anim_set_path_cb(&ginfo.a, anim_path_bezier3_cb);
refer_chart_cubic_bezier();
}
static int32_t anim_path_bezier3_cb(const lv_anim_t * a)
{
uint32_t t = lv_map(a->act_time, 0, a->duration, 0, 1024);
int32_t step = lv_bezier3(t, 0, ginfo.p1, ginfo.p2, 1024);
int32_t new_value;
new_value = step * (a->end_value - a->start_value);
new_value = new_value >> 10;
new_value += a->start_value;
return new_value;
}
static void refer_chart_cubic_bezier(void)
{
for(uint16_t i = 0; i <= CHART_POINTS_NUM; i ++) {
uint32_t t = i * (1024 / CHART_POINTS_NUM);
int32_t step = lv_bezier3(t, 0, ginfo.p1, ginfo.p2, 1024);
lv_chart_set_value_by_id2(ginfo.chart, ginfo.ser1, i, t, step);
}
lv_chart_refresh(ginfo.chart);
}
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_style_translate_x(var, v, LV_PART_MAIN);
}
static void run_button_event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_CLICKED) {
lv_anim_start(&ginfo.a);
}
}
static void slider_event_cb(lv_event_t * e)
{
char buf[16];
lv_obj_t * label;
lv_obj_t * slider = lv_event_get_target(e);
if(slider == ginfo.p1_slider) {
label = ginfo.p1_label;
ginfo.p1 = lv_slider_get_value(slider);
lv_snprintf(buf, sizeof(buf), "p1:%d", ginfo.p1);
}
else {
label = ginfo.p2_label;
ginfo.p2 = lv_slider_get_value(slider);
lv_snprintf(buf, sizeof(buf), "p2:%d", ginfo.p2);
}
lv_label_set_text(label, buf);
refer_chart_cubic_bezier();
}
static void page_obj_init(lv_obj_t * par)
{
ginfo.anim_obj = lv_obj_create(par);
lv_obj_set_size(ginfo.anim_obj, 30, 30);
lv_obj_set_align(ginfo.anim_obj, LV_ALIGN_TOP_LEFT);
lv_obj_remove_flag(ginfo.anim_obj, LV_OBJ_FLAG_SCROLLABLE);
lv_obj_set_style_bg_color(ginfo.anim_obj, lv_palette_main(LV_PALETTE_RED), LV_PART_MAIN);
lv_obj_set_grid_cell(ginfo.anim_obj, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 0, 1);
ginfo.p1_label = lv_label_create(par);
ginfo.p2_label = lv_label_create(par);
lv_label_set_text(ginfo.p1_label, "p1:0");
lv_label_set_text(ginfo.p2_label, "p2:0");
lv_obj_set_grid_cell(ginfo.p1_label, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 1, 1);
lv_obj_set_grid_cell(ginfo.p2_label, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 2, 1);
ginfo.p1_slider = lv_slider_create(par);
ginfo.p2_slider = lv_slider_create(par);
lv_slider_set_range(ginfo.p1_slider, 0, 1024);
lv_slider_set_range(ginfo.p2_slider, 0, 1024);
lv_obj_set_style_pad_all(ginfo.p1_slider, 2, LV_PART_KNOB);
lv_obj_set_style_pad_all(ginfo.p2_slider, 2, LV_PART_KNOB);
lv_obj_add_event_cb(ginfo.p1_slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_add_event_cb(ginfo.p2_slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_grid_cell(ginfo.p1_slider, LV_GRID_ALIGN_STRETCH, 1, 1, LV_GRID_ALIGN_START, 1, 1);
lv_obj_set_grid_cell(ginfo.p2_slider, LV_GRID_ALIGN_STRETCH, 1, 1, LV_GRID_ALIGN_START, 2, 1);
ginfo.run_btn = lv_button_create(par);
lv_obj_add_event_cb(ginfo.run_btn, run_button_event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t * btn_label = lv_label_create(ginfo.run_btn);
lv_label_set_text(btn_label, LV_SYMBOL_PLAY);
lv_obj_center(btn_label);
lv_obj_set_grid_cell(ginfo.run_btn, LV_GRID_ALIGN_STRETCH, 2, 1, LV_GRID_ALIGN_STRETCH, 1, 2);
ginfo.chart = lv_chart_create(par);
lv_obj_set_style_pad_all(ginfo.chart, 0, LV_PART_MAIN);
lv_obj_set_style_size(ginfo.chart, 0, 0, LV_PART_INDICATOR);
lv_chart_set_type(ginfo.chart, LV_CHART_TYPE_SCATTER);
ginfo.ser1 = lv_chart_add_series(ginfo.chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_set_range(ginfo.chart, LV_CHART_AXIS_PRIMARY_Y, 0, 1024);
lv_chart_set_range(ginfo.chart, LV_CHART_AXIS_PRIMARY_X, 0, 1024);
lv_chart_set_point_count(ginfo.chart, CHART_POINTS_NUM);
lv_obj_set_grid_cell(ginfo.chart, LV_GRID_ALIGN_STRETCH, 0, 3, LV_GRID_ALIGN_STRETCH, 3, 1);
}
#endif
Animation timeline
C code
View on GitHub#include "../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
static const int32_t obj_width = 90;
static const int32_t obj_height = 70;
static void set_width(lv_anim_t * var, int32_t v)
{
lv_obj_set_width(var->var, v);
}
static void set_height(lv_anim_t * var, int32_t v)
{
lv_obj_set_height(var->var, v);
}
static void set_slider_value(lv_anim_t * var, int32_t v)
{
lv_slider_set_value(var->var, v, LV_ANIM_OFF);
}
static void btn_start_event_handler(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_current_target_obj(e);
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
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_pause_event_handler(lv_event_t * e)
{
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
lv_anim_timeline_pause(anim_timeline);
}
static void slider_prg_event_handler(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_current_target_obj(e);
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
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)
{
/* Create anim timeline */
lv_anim_timeline_t * anim_timeline = lv_anim_timeline_create();
lv_obj_t * par = lv_screen_active();
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_button_create(par);
lv_obj_add_event_cb(btn_start, btn_start_event_handler, LV_EVENT_VALUE_CHANGED, anim_timeline);
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_pause */
lv_obj_t * btn_pause = lv_button_create(par);
lv_obj_add_event_cb(btn_pause, btn_pause_event_handler, LV_EVENT_CLICKED, anim_timeline);
lv_obj_add_flag(btn_pause, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(btn_pause, LV_ALIGN_TOP_MID, 100, 20);
lv_obj_t * label_pause = lv_label_create(btn_pause);
lv_label_set_text(label_pause, "Pause");
lv_obj_center(label_pause);
/* 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, anim_timeline);
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, LV_ANIM_TIMELINE_PROGRESS_MAX);
/* create 3 objects */
lv_obj_t * obj1 = lv_obj_create(par);
lv_obj_set_size(obj1, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj1, LV_SCROLLBAR_MODE_OFF);
lv_obj_t * obj2 = lv_obj_create(par);
lv_obj_set_size(obj2, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj2, LV_SCROLLBAR_MODE_OFF);
lv_obj_t * obj3 = lv_obj_create(par);
lv_obj_set_size(obj3, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj3, LV_SCROLLBAR_MODE_OFF);
/* anim-slider */
lv_anim_t a_slider;
lv_anim_init(&a_slider);
lv_anim_set_var(&a_slider, slider_prg);
lv_anim_set_values(&a_slider, 0, LV_ANIM_TIMELINE_PROGRESS_MAX);
lv_anim_set_custom_exec_cb(&a_slider, set_slider_value);
lv_anim_set_path_cb(&a_slider, lv_anim_path_linear);
lv_anim_set_duration(&a_slider, 700);
/* anim-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_custom_exec_cb(&a1, set_width);
lv_anim_set_path_cb(&a1, lv_anim_path_overshoot);
lv_anim_set_duration(&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_custom_exec_cb(&a2, set_height);
lv_anim_set_path_cb(&a2, lv_anim_path_ease_out);
lv_anim_set_duration(&a2, 300);
/* anim-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_custom_exec_cb(&a3, set_width);
lv_anim_set_path_cb(&a3, lv_anim_path_overshoot);
lv_anim_set_duration(&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_custom_exec_cb(&a4, set_height);
lv_anim_set_path_cb(&a4, lv_anim_path_ease_out);
lv_anim_set_duration(&a4, 300);
/* anim-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_custom_exec_cb(&a5, set_width);
lv_anim_set_path_cb(&a5, lv_anim_path_overshoot);
lv_anim_set_duration(&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_custom_exec_cb(&a6, set_height);
lv_anim_set_path_cb(&a6, lv_anim_path_ease_out);
lv_anim_set_duration(&a6, 300);
/* add animations to timeline */
lv_anim_timeline_add(anim_timeline, 0, &a_slider);
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);
lv_anim_timeline_set_progress(anim_timeline, LV_ANIM_TIMELINE_PROGRESS_MAX);
}
#endif
Events
Click streaks
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
static void short_click_event_cb(lv_event_t * e)
{
LV_LOG_USER("Short clicked");
lv_obj_t * info_label = lv_event_get_user_data(e);
lv_indev_t * indev = lv_event_get_param(e);
uint8_t cnt = lv_indev_get_short_click_streak(indev);
lv_label_set_text_fmt(info_label, "Short click streak: %u", cnt);
}
static void streak_event_cb(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_target(e);
lv_obj_t * label = lv_obj_get_child(btn, 0);
const char * text = lv_event_get_user_data(e);
lv_label_set_text(label, text);
}
void lv_example_event_streak(void)
{
lv_obj_t * info_label = lv_label_create(lv_screen_active());
lv_label_set_text(info_label, "No events yet");
lv_obj_t * btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 50);
lv_obj_center(btn);
lv_obj_add_event_cb(btn, short_click_event_cb, LV_EVENT_SHORT_CLICKED, info_label);
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_SINGLE_CLICKED, "Single clicked");
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_DOUBLE_CLICKED, "Double clicked");
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_TRIPLE_CLICKED, "Triple clicked");
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text(label, "Click me!");
lv_obj_center(label);
}
#endif
Handle multiple events
C code
View on 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_button(void)
{
lv_obj_t * btn = lv_button_create(lv_screen_active());
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_screen_active());
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
Event bubbling
C code
View on 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_bubble(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
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_button_create(cont);
lv_obj_set_size(btn, 70, 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
Draw event
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
static uint32_t size = 0;
static bool size_dec = false;
static void timer_cb(lv_timer_t * timer)
{
lv_obj_invalidate(lv_timer_get_user_data(timer));
if(size_dec) size--;
else size++;
if(size == 50) size_dec = true;
else if(size == 0) size_dec = false;
}
static void event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
if(base_dsc->part == LV_PART_MAIN) {
lv_draw_rect_dsc_t draw_dsc;
lv_draw_rect_dsc_init(&draw_dsc);
draw_dsc.bg_color = lv_color_hex(0xffaaaa);
draw_dsc.radius = LV_RADIUS_CIRCLE;
draw_dsc.border_color = lv_color_hex(0xff5555);
draw_dsc.border_width = 2;
draw_dsc.outline_color = lv_color_hex(0xff0000);
draw_dsc.outline_pad = 3;
draw_dsc.outline_width = 2;
lv_area_t a;
a.x1 = 0;
a.y1 = 0;
a.x2 = size;
a.y2 = size;
lv_area_t obj_coords;
lv_obj_get_coords(obj, &obj_coords);
lv_area_align(&obj_coords, &a, LV_ALIGN_CENTER, 0, 0);
lv_draw_rect(base_dsc->layer, &draw_dsc, &a);
}
}
/**
* Demonstrate the usage of draw event
*/
void lv_example_event_draw(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 200, 200);
lv_obj_center(cont);
lv_obj_add_event_cb(cont, event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(cont, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
lv_timer_create(timer_cb, 30, cont);
}
#endif
Layouts
Flex
A simple row and a column layout with flexbox
C code
View on 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_screen_active());
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_screen_active());
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_button_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_button_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
Arrange items in rows with wrap and even spacing
C code
View on 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_screen_active());
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
Demonstrate flex grow
C code
View on 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_screen_active());
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.
C code
View on 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_screen_active());
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
Demonstrate column and row gap style properties
C code
View on 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_screen_active());
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_duration(&a, 500);
lv_anim_set_playback_duration(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_duration(&a, 3000);
lv_anim_set_playback_duration(&a, 3000);
lv_anim_start(&a);
}
#endif
RTL base direction changes order of the items
C code
View on 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_screen_active());
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
Grid
A simple grid
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* A simple grid
*/
void lv_example_grid_1(void)
{
static int32_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
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_button_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
Demonstrate cell placement and span
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate cell placement and span
*/
void lv_example_grid_2(void)
{
static int32_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
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 grid's -free unit-
C code
View on 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 int32_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 int32_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_screen_active());
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 track placement
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate track placement
*/
void lv_example_grid_4(void)
{
static int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_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_screen_active());
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 column and row gap
C code
View on 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 int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
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_duration(&a, 500);
lv_anim_set_playback_duration(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_duration(&a, 3000);
lv_anim_set_playback_duration(&a, 3000);
lv_anim_start(&a);
}
#endif
Demonstrate RTL direction on grid
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate RTL direction on grid
*/
void lv_example_grid_6(void)
{
static int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
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
Scrolling
Nested scrolling
C code
View on 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_screen_active());
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_button_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
Snapping
C code
View on 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_remove_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_screen_active());
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_button_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_remove_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_screen_active());
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_screen_active());
lv_label_set_text(label, "One scroll");
lv_obj_align_to(label, sw, LV_ALIGN_OUT_BOTTOM_MID, 0, 5);
#endif
}
#endif