marcux 0 Light Poster

Hi all!
I have an drawing area inside a scrolled window.
I use the following to redraw my drawing area:

myDrawingArea.connect("expose-event", self.view_expose)

In function view_expose the redrawing is carried out.
When I open my window the view_expose function is called all the time and my processor goes crazy!
I just want my drawing area to be redrawn when it is partly covered by another window or when the scroll window is draged and similar situations.
As it is now, even if I minimize my window the function still continues to be called.
Should I connect to another event? Is there an event that does what I am after?
How do I solve this?

Many thanks in advance!