code: def OnNodeActivated(self, event):
          
          try:
              node = self.sorted[event.GetIndex()]
          except IndexError, err:
              log.warn(_('Invalid index in node activated: %(index)s'),
                       index=event.GetIndex())
          else:
              wx.PostEvent(
                  self,
                  squaremap.SquareActivationEvent(node=node, point=None,
                                                  map=None)
              )
docs: We have double-clicked for hit enter on a node refocus squaremap to this node