Method
GtkWidgetadd_tick_callback
Declaration [src]
guint
gtk_widget_add_tick_callback (
GtkWidget* widget,
GtkTickCallback callback,
gpointer user_data,
GDestroyNotify notify
)
Description [src]
Queues an animation frame update and adds a callback to be called before each frame.
Until the tick callback is removed, it will be called frequently
(usually at the frame rate of the output device or as quickly as
the application can be repainted, whichever is slower). For this
reason, is most suitable for handling graphics that change every
frame or every few frames. The tick callback does not automatically
imply a relayout or repaint. If you want a repaint or relayout, and
aren’t changing widget properties that would trigger that (for example,
changing the text of a GtkLabel), then you will have to call
gtk_widget_queue_resize() or gtk_widget_queue_draw() yourself.
gdk_frame_clock_get_frame_time() should generally be used
for timing continuous animations and
gdk_frame_timings_get_predicted_presentation_time() if you are
trying to display isolated frames at particular times.
This is a more convenient alternative to connecting directly to the
GdkFrameClock::update signal of GdkFrameClock, since you
don’t have to worry about when a GdkFrameClock is assigned to a widget.
Parameters
callback-
Type:
GtkTickCallbackFunction to call for updating animations.
user_data-
Type:
gpointerData to pass to
callback.The argument can be NULL.The data is owned by the caller of the method. notify-
Type:
GDestroyNotifyFunction to call to free
user_datawhen the callback is removed.
Return value
Type: guint
An id for the connection of this callback. Remove the callback
by passing the id returned from this function to
gtk_widget_remove_tick_callback().