void gtk_widget_set_can_focus ( GtkWidget* widget, gboolean can_focus )
Specifies whether the input focus can enter the widget or any of its children.
Applications should set
FALSE to mark a
widget as for pointer/touch use only.
Note that having
TRUE is only one of the
necessary conditions for being focusable. A widget must
also be sensitive and focusable and not have an ancestor
that is marked as not can-focus in order to receive input focus.
gtk_widget_grab_focus() for actually setting
the input focus on a widget.