signal callback delegate or function to connect
bool callback(cairo.region.Region region, gdk.surface.Surface surface)
region the region that needs to be redrawn (optional)
surface the instance the signal is connected to (optional)
Returns true to indicate that the signal has been handled
Yes.After to execute callback after default handler, No.After to execute before (default)
Signal ID
Connect to Render signal.
Emitted when part of the surface needs to be redrawn.