title: WxPython switch between controls using tab button
body: <p>I have a window contains different kinds of controls.</p>
  
  <pre><code>class FindReplaceWindow(wx.MiniFrame):
    def __init__(self, parent):
      Style = wx.DEFAULT_MINIFRAME_STYLE|wx.SYSTEM_MENU|wx.CLOSE_BOX
      super(FindReplaceWindow, self).__init__(parent, -1, 'Find and Replace', style = Style)
      self.BackgroundColour = wx.WHITE
      self.MaxSize = wx.Size(400,300)
      self.MinSize = self.MaxSize
      self.CenterOnParent()
      self.LabelFind = wx.StaticText(self, label = 'Find')
      self.LabelReplace = wx.StaticText(self, label = 'Replace')
      self.LabelTransparency = wx.StaticText(self, label = 'Transparency')
      self.TextFind = wx.TextCtrl(self, size = (350,20), style = wx.TE_PROCESS_TAB)
      self.TextReplace = wx.TextCtrl(self, size = (350,20), style = wx.TE_PROCESS_TAB)
      self.SearchDirection = wx.RadioBox(self, -1, 'Search Direction',
       size = (110,-1), choices = ('Up','Down'), style = wx.RA_VERTICAL)
      self.SearchMode = wx.RadioBox(self, -1, 'Search Mode',
       size = (110, -1), choices = ('Text','Regex'), style = wx.RA_VERTICAL)
      self.Flags = wx.CheckListBox(self, -1, wx.DefaultPosition,
       (95,-1), ('Ignore Case','Whole Word(s)','Selection Only'), wx.VERTICAL)
      self.ButtonFind = wx.Button(self, wx.ID_FIND, 'Find')
      self.ButtonReplace = wx.Button(self, wx.ID_REPLACE, 'Replace')
      self.ButtonReplaceAll = wx.Button(self, wx.ID_REPLACE_ALL, 'Replace All')
  </code></pre>
  
  <p>How do I switch between them using Tab button?</p>