code: def OnNodeActivated(self, event):
          
          self.activated_node = self.selected_node = event.node
          self.squareMap.SetModel(event.node, self.adapter)
          self.squareMap.SetSelected( event.node )
          if editor:
              if self.SourceShowFile(event.node):
                  if hasattr(event.node,'lineno'):
                      self.sourceCodeControl.GotoLine(event.node.lineno)
          self.RecordHistory()
docs: Double-click or enter on a node in some control...