mirror of
https://github.com/lvgl/lvgl.git
synced 2025-01-28 07:03:00 +08:00
88c485949f
Add lv_<widget>_draw_part_type_t to widgets to precisly describe the hooked drawings. Also add class_p element to lv_obj_draw_part_dsc_t to show what widgets lv_<widget>_draw_part_type_t needs to be used. Related to: https://forum.lvgl.io/t/how-to-add-minor-division-lines-to-a-chart/5366/
77 lines
2.4 KiB
Markdown
77 lines
2.4 KiB
Markdown
```eval_rst
|
|
.. include:: /header.rst
|
|
:github_url: |github_link_base|/widgets/checkbox.md
|
|
```
|
|
# Checkbox (lv_checkbox)
|
|
|
|
|
|
## Overview
|
|
|
|
The Checkbox object is created from a "tick box" and a label. When the Chackbox is clicked the tick box is toggled.
|
|
|
|
## Parts and Styles
|
|
- `LV_PART_MAIN` The is the background of the Checkbox and it uses the text and all the typical backround style properties.
|
|
`pad_column` adjusts the spacing between the tickbox and the label
|
|
- `LV_PART_INDICATOR` The "tick box" is a square that uses all the typical backround style properties.
|
|
By default its size is equal to the height of the main part's font. Padding properties make the tick box larger in the respective directions.
|
|
|
|
The Checkbox is added to the default group (if it is set).
|
|
|
|
## Usage
|
|
|
|
|
|
### Text
|
|
The text can be modified with the `lv_checkbox_set_text(cb, "New text")` function and will be dynamically allocated.
|
|
|
|
To set a static text,
|
|
use `lv_checkbox_set_static_text(cb, txt)`. This way, only a pointer to `txt` will be stored. The text then shouldn't be deallocated while the checkbox exists.
|
|
|
|
### Check, uncheck, disable
|
|
You can manually check, un-check, and disable the Checkbox by using the common state add/clear function:
|
|
```c
|
|
lv_obj_add_state(cb, LV_STATE_CHECKED); /*Make the chekbox checked*/
|
|
lv_obj_clear_state(cb, LV_STATE_CHECKED); /*MAke the checkbox unchecked*/
|
|
lv_obj_add_state(cb, LV_STATE_CHECKED | LV_STATE_DISABLED); /*Make the checkbox checked and disabled*/
|
|
```
|
|
|
|
## Events
|
|
- `LV_EVENT_VALUE_CHANGED` Sent when the checkbox is toggled.
|
|
- `LV_EVENT_DRAW_PART_BEGIN` and `LV_EVENT_DRAW_PART_END` are sent for the following types:
|
|
- `LV_CHECKBOX_DRAW_PART_BOX` The tickbox of the checkbox
|
|
- `part`: `LV_PART_INDICATOR`
|
|
- `draw_area`: the area of the tickbox
|
|
- `rect_dsc`
|
|
|
|
See the events of the [Base object](/widgets/obj) too.
|
|
|
|
Learn more about [Events](/overview/event).
|
|
|
|
|
|
## Keys
|
|
The following *Keys* are processed by the 'Buttons':
|
|
- `LV_KEY_RIGHT/UP` Go to toggled state if toggling is enabled
|
|
- `LV_KEY_LEFT/DOWN` Go to non-toggled state if toggling is enabled
|
|
- `LV_KEY_ENTER` Clicks the checkbox and toggles it
|
|
|
|
Note that, as usual, the state of `LV_KEY_ENTER` is translated to `LV_EVENT_PRESSED/PRESSING/RELEASED` etc.
|
|
|
|
Learn more about [Keys](/overview/indev).
|
|
|
|
|
|
## Example
|
|
|
|
```eval_rst
|
|
|
|
.. include:: ../../../examples/widgets/checkbox/index.rst
|
|
|
|
```
|
|
|
|
## API
|
|
|
|
```eval_rst
|
|
|
|
.. doxygenfile:: lv_checkbox.h
|
|
:project: lvgl
|
|
|
|
```
|