import wx

# wx.Frame(parent, id=ID_ANY, title=EmptyString, pos=DefaultPosition, size=DefaultSize, style=DEFAULT_FRAME_STYLE, name=FrameNameStr)
# wx.Panel(parent, id=ID_ANY, pos=DefaultPosition, size=DefaultSize, style=TAB_TRAVERSAL, name=PanelNameStr)
# wx.TextCtrl(parent, id=ID_ANY, value=EmptyString, pos=DefaultPosition, size=DefaultSize, style=0, validator=DefaultValidator, name=TextCtrlNameStr)


class Frame_With_FrameSizer_And_PanelSizer(wx.Frame):

    def __init__(self, parent, id=wx.ID_ANY, title=wx.EmptyString, pos=wx.DefaultPosition, size=wx.DefaultSize, style=wx.DEFAULT_FRAME_STYLE, name=wx.FrameNameStr):
        wx.Frame.__init__(self, parent, id, title, pos, size, style, name)

        self.MainPanel = wx.Panel(self)

        self.mainTextSubWindow = wx.TextCtrl(self.MainPanel, style=wx.TE_MULTILINE )

        # Layout

        # The textctrl is a child of the panel, not the frame.
        # So add the textctrl to a sizer that is an attribute of the panel, not of the frame

        # This sizer is necessary if the panel widget, has more then one child widget.
        # In general I always do it anyway.
        panel_sizer = wx.BoxSizer(wx.VERTICAL)
        panel_sizer.Add(self.mainTextSubWindow, 1, wx.EXPAND)
        self.MainPanel.SetSizer(panel_sizer) 

        # This sizer is necessary if the frame widget, has more then one child widget,
        # In general I always do it anyway.
        frame_sizer = wx.BoxSizer(wx.VERTICAL)
        frame_sizer.Add(self.MainPanel, 1, wx.EXPAND)
        self.SetSizer(frame_sizer)

        self.Show()


if __name__ == "__main__":
    app = wx.App()
    frame = Frame_With_FrameSizer_And_PanelSizer(None, title='Frame Sizer plus Panel Sizer')
    app.MainLoop()