widget
defined by x
, y
,
width
and height
by calling gdkWindowInvalidateRect
on the
widget's window and all its child windows. Once the main loop
becomes idle (after the current batch of events has been processed,
roughly), the window will receive expose events for the union of
all regions that have been invalidated.gtkWidgetQueueDrawArea(object, x, y, width, height)
object
x
y
width
height
gdkWindowInvalidateRect
directly, to schedule a redraw of a
GtkDrawingArea
or some portion thereof.
Frequently you can just call gdkWindowInvalidateRect
or
gdkWindowInvalidateRegion
instead of this function. Those
functions will invalidate only a single window, instead of the
widget and all its children.
The advantage of adding to the invalidated region compared to
simply drawing immediately is efficiency; using an invalid region
ensures that you only have to redraw one time.