# Objective
Accessibility features don't work with the UI `button` example because
`InputFocus` must be set for the accessibility systems to recognise the
button.
Fixes#18760
## Solution
* Set the button entity as the `InputFocus` when it is hovered or
pressed.
* Call `set_changed` on the `Button` component when the button's state
changes to hovered or pressed (the accessibility system's only update
the button's state when the `Button` component is marked as changed).
## Testing
Install NVDA, it should say "hover" when the button is hovered and
"pressed" when the button is pressed.
The bounds of the accessibility node are reported incorrectly. I thought
we fixed this, I'll take another look at it. It's not a problem with
this PR.