draw
Description:
This signal is emitted when a widget is supposed to render itself.
The widget
's top left corner must be painted at the origin of the passed in context and be sized to the values returned by
get_allocated_width and
get_allocated_height.
Signal handlers connected to this signal can modify the cairo context passed as cr
in any way they like and don't need to restore
it. The signal emission takes care of calling save before and
restore after invoking the handler.
The signal handler will get a cr
with a clip region already set to the widget's dirty region, i.e. to the area that needs
repainting. Complicated widgets that want to avoid redrawing themselves completely can get the full extents of the clip region with
cairo_get_clip_rectangle, or they can get a finer-grained representation
of the dirty region with copy_clip_rectangle_list.
Parameters:
cr |
the cairo context to draw to |
Returns:
true to stop other handlers from being invoked for the event. false to propagate the event further. |