wxPython中listctrl的双击事件问题。

import wx

class ListCtrlFrame(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, None, -1,"ListCtrl",size=(200,200))
        self.list = wx.ListCtrl(self, -1, style=wx.LC_LIST|wx.LC_EDIT_LABELS)
        for x in range(10):
            self.list.InsertStringItem(x,"This is item %02d" % x)
         
         
        self.list.Bind(wx.EVT_LIST_ITEM_SELECTED,self.OnLeftClick)
        self.list.Bind(wx.EVT_LIST_ITEM_ACTIVATED,self.OnDclick)
         
        
        
    def OnLeftClick(self,event):
        wx.MessageBox("Single Cilcked","Single cilck",wx.YES_NO)
        
    def OnDclick(self,event):
        wx.MessageBox("Double Cilcked","Double cilck",wx.YES_NO)
        
            
app = wx.PySimpleApp()
frame = ListCtrlFrame()
frame.Show()
app.MainLoop()