title: pygtk: overriding gtk.Paned.compute_position
body: <p>I have a HPaned that one of its children changes its size requirement frequently, since its text changes. The result is that the pane moves every time the text is changed. I'd like to override the Paned.compute_position method so that the size of the child will not decrease, just increase. However, I can't find a way to override it. Even</p>
  
  <pre><code>class MyHPaned(gtk.HPaned):
      def do_compute_position(self, allocation, child1_req, child2_req):
          print "Hi"
          return gtk.HPaned.compute_position(self, allocation, child1_req, child2_req)
  gobject.type_register(MyHPaned)
  </code></pre>
  
  <p>doesn't work. Do you have a suggestion? Thanks!</p>