lvgl/docs/widgets/core/checkbox.md

```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 the uses all the typical backround style properties. 
By deafult its size is equal to the height of the main part's font. Padding properties makes the tick boy larger in the respectiev directions.

The Checkbox is added to the deafult group (if it is set). 

## Usage


### Text
The text can be modified by the `lv_checkbox_set_text(cb, "New text")` function. 
It will dynamically allocate the text.

To set a static text, 
use `lv_checkbox_set_static_text(cb, txt)`. This way, only a pointer of `txt` will be stored and it 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 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 both main and indicator parts to allow hooking the drawing. 
The for more detail on the main part see the [Base object](/widgets/obj#events)'s documentation.
For the indicator the following fields are used: `clip_area`, `draw_area`, `rect_dsc`, `part`. 

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

```