grab_focus

Causes this to have the keyboard focus for the `GtkWindow` it's inside.

If this is not focusable, or its [vfunc@Gtk.Widget.grab_focus] implementation cannot transfer the focus to a descendant of this that is focusable, it will not take focus and false will be returned.

Calling [method@Gtk.Widget.grab_focus] on an already focused widget is allowed, should not have an effect, and return true.

Parameters:

this	a `GtkWidget`

Returns:

true if focus is now inside this.