GdkFrameClock* gtk_widget_get_frame_clock ( GtkWidget* widget )
Obtains the frame clock for a widget.
The frame clock is a global “ticker” that can be used to drive animations and repaints. The most common reason to get the frame clock is to call gdk_frame_clock_get_frame_time(), in order to get a time to use for animating. For example you might record the start of the animation with an initial value from gdk_frame_clock_get_frame_time(), and then update the animation by calling gdk_frame_clock_get_frame_time() again during each repaint.
gdk_frame_clock_request_phase() will result in a new frame on the clock, but won’t necessarily repaint any widgets. To repaint a widget, you have to use gtk_widget_queue_draw() which invalidates the widget (thus scheduling it to receive a draw on the next frame). gtk_widget_queue_draw() will also end up requesting a frame on the appropriate frame clock.
A widget’s frame clock will not change while the widget is mapped. Reparenting a widget (which implies a temporary unmap) can change the widget’s frame clock.
Unrealized widgets do not have a frame clock.