Can I shrink an GtkDrawingArea?

[airship <wxingyan gmail com>]

Hi,

I put a GtkDrawingArea in a GtkWindow to draw something,so i use
gtk_widget_set_size_request() to set the size of GtkDrawingArea,but
after I did that,I found that I can't shrink the main window.

How can i make the GtkDrawingArea to be enlarged or shrinked as the main
window ? Is it possible?

I have to override the expose_event cause I have to do some animation
stuff. Do I have some other choice beside using GtkDrawingArea?

Thanks in advance~