canvas widget resize

[control H <control h gmail com>]

Hi I'm experimenting with goocanvas (2.0). For my application I don't
put the canvas inside a scrolled window but inside a vbox. The problem
arises that when I connect to a 'configure-event' signal I don't
receive anything. So how can I change the canvas size and redraw some
item myself as soon as the vbox resizes?

My objective is to put one item onto the canvas that serves as a
background. All other items are regular canvas items on top of that
background item.

Thanks for your input.