uint* handle = (uint*)Gdk.X11Window.get_xid(widget.get_window());
 playbin = Gst.ElementFactory.make("playbin","player");
            playbin.bus.add_watch(0,(bus,message) => {
                if(Gst.Video.is_video_overlay_prepare_window_handle_message(message))
                    (message.src as Gst.Video.Overlay).set_window_handle(handle);
                return true;
            });