Button matrix (lv_btnmatrix)¶
Overview¶
The Button Matrix object is a lightweight way to display multiple buttons in rows and columns. Lightweight because the buttons are not actually created but just virtually drawn on the fly. This way, one button use only eight extra bytes of memory instead of the ~100-150 bytes a normal Button object plus the 100 or so bytes for the Label object.
The Button matrix is added to the default group (if one is set). Besides the Button matrix is an editable object to allow selecting and clicking the buttons with encoder navigation too.
Parts and Styles¶
LV_PART_MAIN
The background of the button matrix, uses the typical background style properties.pad_row
andpad_column
sets the space between the buttons.LV_PART_ITEMS
The buttons all use the text and typical background style properties except translations and transformations.
Usage¶
Button's text¶
There is a text on each button. To specify them a descriptor string array, called map, needs to be used.
The map can be set with lv_btnmatrix_set_map(btnm, my_map)
.
The declaration of a map should look like const char * map[] = {"btn1", "btn2", "btn3", NULL}
.
Note that the last element has to be either NULL
or an empty string (""
)!
Use "\n"
in the map to insert a line break. E.g. {"btn1", "btn2", "\n", "btn3", ""}
. Each line's buttons have their width calculated automatically.
So in the example the first row will have 2 buttons each with 50% width and a second row with 1 button having 100% width.
Control buttons¶
The buttons' width can be set relative to the other button in the same row with lv_btnmatrix_set_btn_width(btnm, btn_id, width)
E.g. in a line with two buttons: btnA, width = 1 and btnB, width = 2, btnA will have 33 % width and btnB will have 66 % width.
It's similar to how the flex-grow
property works in CSS.
The width must be in the [1..7] range and the default width is 1.
In addition to the width, each button can be customized with the following parameters:
LV_BTNMATRIX_CTRL_HIDDEN
Makes a button hidden (hidden buttons still take up space in the layout, they are just not visible or clickable)LV_BTNMATRIX_CTRL_NO_REPEAT
Disable repeating when the button is long pressedLV_BTNMATRIX_CTRL_DISABLED
Makes a button disabled LikeLV_STATE_DISABLED
on normal objectsLV_BTNMATRIX_CTRL_CHECKABLE
Enable toggling of a button. I.e.LV_STATE_CHECHED
will be added/removed as the button is clickedLV_BTNMATRIX_CTRL_CHECKED
Make the button checked. It will use theLV_STATE_CHECHKED
styles.LV_BTNMATRIX_CTRL_CLICK_TRIG
Enabled: send LV_EVENT_VALUE_CHANGE on CLICK, Disabled: send LV_EVENT_VALUE_CHANGE on PRESSLV_BTNMATRIX_CTRL_POPOVER
Show the button label in a popover when pressing this keyLV_BTNMATRIX_CTRL_RECOLOR
Enable recoloring of button texts with#
. E.g."It's #ff0000 red#"
LV_BTNMATRIX_CTRL_CUSTOM_1
Custom free to use flagLV_BTNMATRIX_CTRL_CUSTOM_2
Custom free to use flag
By default, all flags are disabled.
To set or clear a button's control attribute, use lv_btnmatrix_set_btn_ctrl(btnm, btn_id, LV_BTNM_CTRL_...)
and
lv_btnmatrix_clear_btn_ctrl(btnm, btn_id, LV_BTNMATRIX_CTRL_...)
respectively. More LV_BTNM_CTRL_...
values can be OR-ed
To set/clear the same control attribute for all buttons of a button matrix, use lv_btnmatrix_set_btn_ctrl_all(btnm, LV_BTNM_CTRL_...)
and
lv_btnmatrix_clear_btn_ctrl_all(btnm, LV_BTNMATRIX_CTRL_...)
.
The set a control map for a button matrix (similarly to the map for the text), use lv_btnmatrix_set_ctrl_map(btnm, ctrl_map)
.
An element of ctrl_map
should look like ctrl_map[0] = width | LV_BTNM_CTRL_NO_REPEAT | LV_BTNM_CTRL_CHECHKABLE
.
The number of elements should be equal to the number of buttons (excluding newlines characters).
One check¶
The "One check" feature can be enabled with lv_btnmatrix_set_one_checked(btnm, true)
to allow only one button to be checked at a time.
Events¶
LV_EVENT_VALUE_CHANGED
Sent when a button is pressed/released or repeated after long press. The event parameter is set to the ID of the pressed/released button.LV_EVENT_DRAW_PART_BEGIN
andLV_EVENT_DRAW_PART_END
are sent for the following types:LV_BTNMATRIX_DRAW_PART_BTN
The individual buttons.part
:LV_PART_ITEMS
id
:index of the button being drawndraw_area
: the area of teh buttonrect_dsc
See the events of the Base object too.
lv_btnmatrix_get_selected_btn(btnm)
returns the index of the most recently released or focused button or LV_BTNMATRIX_BTN_NONE
if no such button.
lv_btnmatrix_get_btn_text(btnm, btn_id)
returns a pointer to the text of btn_id
th button.
Learn more about Events.
Keys¶
LV_KEY_RIGHT/UP/LEFT/RIGHT
To navigate among the buttons to select oneLV_KEY_ENTER
To press/release the selected button
Learn more about Keys.
Example¶
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_param(e);
/*Change the draw descriptor 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 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_param(e);
/*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()
API¶
Typedefs
-
typedef uint16_t lv_btnmatrix_ctrl_t¶
Enums
-
enum [anonymous]¶
Type to store button control bits (disabled, hidden etc.) The first 3 bits are used to store the width
Values:
-
enumerator _LV_BTNMATRIX_WIDTH¶
Reserved to stire the size units
-
enumerator LV_BTNMATRIX_CTRL_HIDDEN¶
Button hidden
-
enumerator LV_BTNMATRIX_CTRL_NO_REPEAT¶
Do not repeat press this button.
-
enumerator LV_BTNMATRIX_CTRL_DISABLED¶
Disable this button.
-
enumerator LV_BTNMATRIX_CTRL_CHECKABLE¶
The button can be toggled.
-
enumerator LV_BTNMATRIX_CTRL_CHECKED¶
Button is currently toggled (e.g. checked).
-
enumerator LV_BTNMATRIX_CTRL_CLICK_TRIG¶
1: Send LV_EVENT_VALUE_CHANGE on CLICK, 0: Send LV_EVENT_VALUE_CHANGE on PRESS
-
enumerator LV_BTNMATRIX_CTRL_POPOVER¶
Show a popover when pressing this key
-
enumerator LV_BTNMATRIX_CTRL_RECOLOR¶
Enable text recoloring with
#color
-
enumerator _LV_BTNMATRIX_CTRL_RESERVED¶
Reserved for later use
-
enumerator LV_BTNMATRIX_CTRL_CUSTOM_1¶
Custom free to use flag
-
enumerator LV_BTNMATRIX_CTRL_CUSTOM_2¶
Custom free to use flag
-
enumerator _LV_BTNMATRIX_WIDTH¶
Functions
-
LV_EXPORT_CONST_INT(LV_BTNMATRIX_BTN_NONE)¶
-
lv_obj_t *lv_btnmatrix_create(lv_obj_t *parent)¶
Create a button matrix object
- Parameters
parent -- pointer to an object, it will be the parent of the new button matrix
- Returns
pointer to the created button matrix
-
void lv_btnmatrix_set_map(lv_obj_t *obj, const char *map[])¶
Set a new map. Buttons will be created/deleted according to the map. The button matrix keeps a reference to the map and so the string array must not be deallocated during the life of the matrix.
- Parameters
obj -- pointer to a button matrix object
map -- pointer a string array. The last string has to be: "". Use "\n" to make a line break.
-
void lv_btnmatrix_set_ctrl_map(lv_obj_t *obj, const lv_btnmatrix_ctrl_t ctrl_map[])¶
Set the button control map (hidden, disabled etc.) for a button matrix. The control map array will be copied and so may be deallocated after this function returns.
- Parameters
obj -- pointer to a button matrix object
ctrl_map -- pointer to an array of
lv_btn_ctrl_t
control bytes. The length of the array and position of the elements must match the number and order of the individual buttons (i.e. excludes newline entries). An element of the map should look like e.g.:ctrl_map[0] = width | LV_BTNMATRIX_CTRL_NO_REPEAT | LV_BTNMATRIX_CTRL_TGL_ENABLE
-
void lv_btnmatrix_set_selected_btn(lv_obj_t *obj, uint16_t btn_id)¶
Set the selected buttons
- Parameters
obj -- pointer to button matrix object
btn_id -- 0 based index of the button to modify. (Not counting new lines)
-
void lv_btnmatrix_set_btn_ctrl(lv_obj_t *obj, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)¶
Set the attributes of a button of the button matrix
- Parameters
obj -- pointer to button matrix object
btn_id -- 0 based index of the button to modify. (Not counting new lines)
ctrl -- OR-ed attributs. E.g.
LV_BTNMATRIX_CTRL_NO_REPEAT | LV_BTNMATRIX_CTRL_CHECKABLE
-
void lv_btnmatrix_clear_btn_ctrl(lv_obj_t *obj, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)¶
Clear the attributes of a button of the button matrix
- Parameters
obj -- pointer to button matrix object
btn_id -- 0 based index of the button to modify. (Not counting new lines)
ctrl -- OR-ed attributs. E.g.
LV_BTNMATRIX_CTRL_NO_REPEAT | LV_BTNMATRIX_CTRL_CHECKABLE
-
void lv_btnmatrix_set_btn_ctrl_all(lv_obj_t *obj, lv_btnmatrix_ctrl_t ctrl)¶
Set attributes of all buttons of a button matrix
- Parameters
obj -- pointer to a button matrix object
ctrl -- attribute(s) to set from
lv_btnmatrix_ctrl_t
. Values can be ORed.
-
void lv_btnmatrix_clear_btn_ctrl_all(lv_obj_t *obj, lv_btnmatrix_ctrl_t ctrl)¶
Clear the attributes of all buttons of a button matrix
- Parameters
obj -- pointer to a button matrix object
ctrl -- attribute(s) to set from
lv_btnmatrix_ctrl_t
. Values can be ORed.en -- true: set the attributes; false: clear the attributes
-
void lv_btnmatrix_set_btn_width(lv_obj_t *obj, uint16_t btn_id, uint8_t width)¶
Set a single button's relative width. This method will cause the matrix be regenerated and is a relatively expensive operation. It is recommended that initial width be specified using
lv_btnmatrix_set_ctrl_map
and this method only be used for dynamic changes.- Parameters
obj -- pointer to button matrix object
btn_id -- 0 based index of the button to modify.
width -- relative width compared to the buttons in the same row. [1..7]
-
void lv_btnmatrix_set_one_checked(lv_obj_t *obj, bool en)¶
Make the button matrix like a selector widget (only one button may be checked at a time).
LV_BTNMATRIX_CTRL_CHECKABLE
must be enabled on the buttons to be selected usinglv_btnmatrix_set_ctrl()
orlv_btnmatrix_set_btn_ctrl_all()
.- Parameters
obj -- pointer to a button matrix object
en -- whether "one check" mode is enabled
-
const char **lv_btnmatrix_get_map(const lv_obj_t *obj)¶
Get the current map of a button matrix
- Parameters
obj -- pointer to a button matrix object
- Returns
the current map
-
uint16_t lv_btnmatrix_get_selected_btn(const lv_obj_t *obj)¶
Get the index of the lastly "activated" button by the user (pressed, released, focused etc) Useful in the
event_cb
to get the text of the button, check if hidden etc.- Parameters
obj -- pointer to button matrix object
- Returns
index of the last released button (LV_BTNMATRIX_BTN_NONE: if unset)
-
const char *lv_btnmatrix_get_btn_text(const lv_obj_t *obj, uint16_t btn_id)¶
Get the button's text
- Parameters
obj -- pointer to button matrix object
btn_id -- the index a button not counting new line characters.
- Returns
text of btn_index` button
-
bool lv_btnmatrix_has_btn_ctrl(lv_obj_t *obj, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)¶
Get the whether a control value is enabled or disabled for button of a button matrix
- Parameters
obj -- pointer to a button matrix object
btn_id -- the index of a button not counting new line characters.
ctrl -- control values to check (ORed value can be used)
- Returns
true: the control attribute is enabled false: disabled
Variables
-
const lv_obj_class_t lv_btnmatrix_class¶
-
struct lv_btnmatrix_t¶