setFocusable
Specifies whether @widget can own the input focus.
Widget implementations should set @focusable to true in their init() function if they want to receive keyboard input.
Note that having @focusable be true is only one of the necessary conditions for being focusable. A widget must also be sensitive and can-focus and not have an ancestor that is marked as not can-focus in order to receive input focus.
See method@Gtk.Widget.grab_focus for actually setting the input focus on a widget.
Parameters
focusable
whether or not @widget can own the input focus