hi. I am rather new to wx/python so please excuse if this is stupid or ill described.

I am substituting a nested sizer with a new one as shown in the snippet below. after some tinkering everything seems to work out but the re-drawing of the parent-sizer. the content of the old nested sizer remains and gets "painted" over with the new sizer content despite my sizer.Layout()

system setup:
- python 2.5.5.2 and 2.6.4
- wxpython 2.8

-- coding: utf8 --

import wx

class Frame(wx.Frame):
    def init(self):
        wx.Frame.init(self, None, wx.ID_ANY, title='test')

class Test(wx.App):
    def OnInit(self):
        frame = Frame()
        self.panel = wx.Panel(frame)
        self.panel.SetBackgroundColour('red')
        self.sizer = wx.BoxSizer(wx.VERTICAL)
        button = wx.Button(self.panel, wx.ID_ANY, 'TEST')

    self.hsizer = wx.BoxSizer(wx.HORIZONTAL)
    self.hsizer.Add(wx.StaticText(self.panel, wx.ID_ANY, 'nacknack'))

    self.sizer.Add(button)
    self.Bind(wx.EVT_BUTTON, self.on_test_button, button)
    self.text = wx.StaticText(self.panel, wx.ID_ANY, 'FOOO')
    self.sizer.Add(self.text)
    self.sizer.Add(self.hsizer)
    self.panel.SetSizer(self.sizer)
    frame.Show()
    return True



def on_test_button(self, evt):
    tmpsizer = wx.BoxSizer(wx.VERTICAL)
    tmpsizer.Add(self.makesizer())
    tmpitem = tmpsizer.GetChildren()[0]


    self.sizer.Replace(2, tmpitem)
    self.sizer.Layout()

def makesizer(self):
    testsizer = wx.BoxSizer(wx.HORIZONTAL)
    testsizer.Add(wx.StaticText(self.panel, wx.ID_ANY, 'testsizer'))
    return testsizer


if __name__ == '__main__':
    app = Test()
    app.MainLoop()