public void grab_keyboard
Grabs keyboard events, after the grab is done keyboard events (#ClutterActor::key-press-event and
key_release_event) are delivered to this actor directly.
The source set in the event will be the actor that would have received the event if the keyboard grab was not in effect.
Like pointer grabs, keyboard grabs should only be used as a last resource.
See also set_key_focus and
grab_key_focus to perform a "soft" key grab and assign key focus to
a specific actor.