lvgl/docs/widgets/core/btn.md

.. include:: /header.rst 
:github_url: |github_link_base|/widgets/btn.md

Button (lv_btn)

Overview

Buttons have no new features compared to the Base object. They are usuful for semantic purposes and have slightly different default settings.

Buttons, by default, differ from Base object in the following ways:

• Not scrollable
• Added to the default group
• Default height and width set to LV_SIZE_CONTENT

Parts and Styles

• LV_PART_MAIN The background of the button. Uses the typical background style properties.

Usage

There are no new features compared to Base object.

Events

• 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.

Learn more about Events.

Keys

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.

Note that the state of LV_KEY_ENTER is translated to LV_EVENT_PRESSED/PRESSING/RELEASED etc.

Learn more about Keys.

Example

.. include:: ../../../examples/widgets/btn/index.rst

API

.. doxygenfile:: lv_btn.h
  :project: lvgl