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51 lines
1.3 KiB
Markdown
51 lines
1.3 KiB
Markdown
```eval_rst
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.. include:: /header.rst
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:github_url: |github_link_base|/widgets/btn.md
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```
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# Button (lv_btn)
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## Overview
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Buttons have no new features compared to the [Base object](/widgets/obj). They are usuful for semantic purposes and have slightly different default settings.
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Buttons, by default, differ from Base object in the following ways:
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- Not scrollable
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- Added to the default group
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- Default height and width set to `LV_SIZE_CONTENT`
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## Parts and Styles
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- `LV_PART_MAIN` The background of the button. Uses the typical background style properties.
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## Usage
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There are no new features compared to [Base object](/widgets/obj).
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## Events
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- `LV_EVENT_VALUE_CHANGED` when the `LV_OBJ_FLAG_CHECKABLE` flag is enabled and the object is clicked. The event happens on transition to/from the checked state.
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Learn more about [Events](/overview/event).
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## Keys
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If `LV_OBJ_FLAG_CHECKABLE` is enabled `LV_KEY_RIGHT` and `LV_KEY_UP` make the object checked, and `LV_KEY_LEFT` and `LV_KEY_DOWN` make it unchecked.
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Note that the state of `LV_KEY_ENTER` is translated to `LV_EVENT_PRESSED/PRESSING/RELEASED` etc.
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Learn more about [Keys](/overview/indev).
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## Example
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```eval_rst
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.. include:: ../../../examples/widgets/btn/index.rst
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```
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## API
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```eval_rst
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.. doxygenfile:: lv_btn.h
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:project: lvgl
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```
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