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lvgl/docs/widgets/imagebutton.rst
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.. _lv_imagebutton:
=============================
Image button (lv_imagebutton)
=============================
Overview
********
The Image button is very similar to the simple 'Button' object. The only
difference is that it displays user-defined images in each state instead
of drawing a rectangle.
You can set a left, right and center image, and the center image will be
repeated to match the width of the object.
.. _lv_imagebutton_parts_and_styles:
Parts and Styles
****************
- :cpp:enumerator:`LV_PART_MAIN` Refers to the image(s). If background style
properties are used, a rectangle will be drawn behind the image
button.
.. _lv_imagebutton_usage:
Usage
*****
Image sources
-------------
To set the image in a state, use the
:cpp:expr:`lv_imagebutton_set_src(imagebutton, LV_IMAGEBUTTON_STATE_..., src_left, src_center, src_right)`.
The image sources work the same as described in the `Image object </widgets/image>`__
except that "Symbols" are not supported by the Image button. Any of the sources can ``NULL``.
If only ``src_center`` is specified, the width of the widget will be set automatically to the
width of the image. However, if all three sources are set, the width needs to be set by the user
(using e.g. :cpp:expr:`lv_obj_set_width`) and the center image will be tiled to fill the given size.
The possible states are:
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_RELEASED`
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_PRESSED`
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_DISABLED`
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_CHECKED_RELEASED`
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_CHECKED_PRESSED`
- :cpp:enumerator:`LV_IMAGEBUTTON_STATE_CHECKED_DISABLED`
If you set sources only in :cpp:enumerator:`LV_IMAGEBUTTON_STATE_RELEASED`, these sources
will be used in other states too. If you set e.g. :cpp:enumerator:`LV_IMAGEBUTTON_STATE_PRESSED`
they will be used in pressed state instead of the released images.
States
------
Instead of the regular :cpp:func:`lv_obj_add_state` and :cpp:func:`lv_obj_remove_state` functions,
the :cpp:expr:`lv_imagebutton_set_state(imagebutton, LV_IMAGEBUTTON_STATE_...)` function should be
used to manually set a state.
.. _lv_imagebutton_events:
Events
******
- :cpp:enumerator:`LV_EVENT_VALUE_CHANGED` Sent when the button is toggled.
Learn more about :ref:`events`.
.. _lv_imagebutton_keys:
Keys
****
- ``LV_KEY_RIGHT/UP`` Go to toggled state if :cpp:enumerator:`LV_OBJ_FLAG_CHECKABLE`
is enabled.
- ``LV_KEY_LEFT/DOWN`` Go to non-toggled state if
:cpp:enumerator:`LV_OBJ_FLAG_CHECKABLE` is enabled.
- :cpp:enumerator:`LV_KEY_ENTER` Clicks the button
Learn more about :ref:`indev_keys`.
.. _lv_imagebutton_example:
Example
*******
.. include:: ../examples/widgets/imagebutton/index.rst
.. _lv_imagebutton_api:
API
***