title: How can I get a list of windows with Wnck, using PyGI?
body: <p>I just started using PyGI (on Ubuntu Natty), although I have never used pygtk before.
  I have used wnck in a wxPython program though, and it was easy enough to get a list of currently opened windows. From PyGI, the window list is always empty.
  relevant code bits:</p>
  
  <pre><code>from gi.repository import Gtk, Wnck
  
  while Gtk.events_pending():
      Gtk.main_iteration()
  #... in my app class...
      screen = Wnck.Screen.get_default()
      wins = screen.get_windows()
  </code></pre>
  
  <p>with that, <code>wins == []</code>.
  Thanks!</p>