Sets @widget as the widget that @bar will capture key events
from.
If key events are handled by the search bar, the bar will
be shown, and the entry populated with the entered text.
Note that despite the name of this function, the events
are only 'captured' in the bubble phase, which means that
editable child widgets of @widget will receive text input
before it gets captured. If that is not desired, you can
capture and forward the events yourself with
[method@Gtk.EventControllerKey.forward].
Sets @widget as the widget that @bar will capture key events from.
If key events are handled by the search bar, the bar will be shown, and the entry populated with the entered text.
Note that despite the name of this function, the events are only 'captured' in the bubble phase, which means that editable child widgets of @widget will receive text input before it gets captured. If that is not desired, you can capture and forward the events yourself with [method@Gtk.EventControllerKey.forward].