Registers a GdkWindow with the widget and sets it up so that
the widget receives events for it. Call gtk_widget_unregister_window()
when destroying the window.
Before 3.8 you needed to call gdk_window_set_user_data() directly to set
this up. This is now deprecated and you should use gtk_widget_register_window()
instead. Old code will keep working as is, although some new features like
transparency might not work perfectly.
Registers a GdkWindow with the widget and sets it up so that the widget receives events for it. Call gtk_widget_unregister_window() when destroying the window. Before 3.8 you needed to call gdk_window_set_user_data() directly to set this up. This is now deprecated and you should use gtk_widget_register_window() instead. Old code will keep working as is, although some new features like transparency might not work perfectly.