using a wx.Simplebook giving me exit code 3221225477

Question

I'm trying to wrap my head around using wx.Simplebook, and as far as I can tell I've basically copied the python demo, but obviously am missing something vital.

This example should be a wx.Frame with two wx.Buttons on the left and the wx.Simplebook on the right. The two buttons should switch between the pages of the book.

import wx


class MainPage (wx.Frame):
    def __init__ (self,parent):
        wx.Frame.__init__ ( self, None, 1, title = "NOTEBOOK", pos= wx.DefaultPosition, size = wx.Size( 320,400 ), style = wx.DEFAULT_FRAME_STYLE|wx.TAB_TRAVERSAL)
        mainSizer = wx.BoxSizer(wx.HORIZONTAL)
        buttonSizer = wx.BoxSizer(wx.VERTICAL)
        pagesSizer = wx.BoxSizer(wx.VERTICAL)
        mainSizer.Add(buttonSizer,1,wx.EXPAND,0)
        mainSizer.Add(pagesSizer,1,wx.EXPAND,0)
        page1Button = wx.Button(self,wx.ID_ANY,"Page 1",wx.DefaultPosition,wx.DefaultSize,0)
        page2Button = wx.Button(self,wx.ID_ANY,"Page 2",wx.DefaultPosition,wx.DefaultSize,0)
        buttonSizer.Add(page1Button,1,0)
        buttonSizer.Add(page2Button,1,0)
        book = MainPage.BookTest(self)
        pagesSizer.Add(book,1,wx.EXPAND)
        self.SetSizer(mainSizer)
        self.Layout()

    class BookTest (wx.Simplebook):
        def __init__(self,parent):
            wx.Simplebook.__init__(self,parent)
            page1=MainPage.Page1(self)
            page2=MainPage.Page2(self)
            self.AddPage(page1,"")
            self.AddPage(page2,"")

    class Page1 (wx.Panel):
        def __init__(self,parent):
            wx.Panel.__init__(self)
            sizer = wx.BoxSizer(wx.VERTICAL)
            t=wx.StaticText(self,-1,"THIS IS PAGE 1")
            sizer.Add(t,1,wx.EXPAND,0)      

    class Page2 (wx.Panel):
        def __init__(self,parent):
            wx.Panel.__init__(self)
            sizer = wx.BoxSizer(wx.VERTICAL)
            t=wx.StaticText(self,-1,"THIS IS PAGE 2")
            sizer.Add(t,1,wx.EXPAND,0)

if __name__ == '__main__':
    app = wx.App()
    frm = MainPage(None)
    frm.Centre()
    frm.Show()
    app.MainLoop()

Half the time the build pauses, and nothing is shown (although I get a 'Finished in 2.0 seconds' message), the other half of the time i get error code 3221225477.

if you # the line pagesSizer.Add(book,1,wx.EXPAND), the frame opens as planned, but obviously without the simplebook. Where have I gone wrong?

Thanks,

Sundown

Answer 1

Welcome to StackOverflow.

Your code is missing just a few details. First, the indentation of the classes is wrong. They should all start in the first column. The code suggests (at least to me) that you are thinking about BookTest, Page1 and Page2 as subclasses of MainPage. But this is not the correct way to think about it. They are all independent classes and you will use in MainPage and instance of BookTest and BookTest will use an instance of Page1 and an instance of Page2.

Changing this leads to change the line book = MainPage.BookTest(self) to book = BookTest(self)

The second problem is that you need to keep track of parent/child relationship for your widgets because this helps a lot to correctly display them. Therefore, you need to pass the parent argument when starting the wx.Simplebook and wx.Panel widget in BookTest and Page1 and Page2.

Here is the code,

import wx


class MainPage (wx.Frame):
    def __init__ (self,parent):
        wx.Frame.__init__ ( self, None, 1, title = "NOTEBOOK", pos= wx.DefaultPosition, size = wx.Size( 320,400 ), style = wx.DEFAULT_FRAME_STYLE|wx.TAB_TRAVERSAL)
        mainSizer = wx.BoxSizer(wx.HORIZONTAL)
        buttonSizer = wx.BoxSizer(wx.VERTICAL)
        pagesSizer = wx.BoxSizer(wx.VERTICAL)
        mainSizer.Add(buttonSizer,1,wx.EXPAND,0)
        mainSizer.Add(pagesSizer,1,wx.EXPAND,0)
        page1Button = wx.Button(self,wx.ID_ANY,"Page 1",wx.DefaultPosition,wx.DefaultSize,0)
        page2Button = wx.Button(self,wx.ID_ANY,"Page 2",wx.DefaultPosition,wx.DefaultSize,0)
        buttonSizer.Add(page1Button,1,0)
        buttonSizer.Add(page2Button,1,0)
        book = BookTest(self)
        pagesSizer.Add(book,1,wx.EXPAND)
        self.SetSizer(mainSizer)
        self.Layout()

class BookTest (wx.Simplebook):
    def __init__(self, parent):
        wx.Simplebook.__init__(self, parent=parent)
        page1=Page1(self)
        page2=Page2(self)
        self.AddPage(page1,"")
        self.AddPage(page2,"")

class Page1 (wx.Panel):
    def __init__(self, parent):
        wx.Panel.__init__(self, parent=parent)
        sizer = wx.BoxSizer(wx.VERTICAL)
        t=wx.StaticText(self,-1,"THIS IS PAGE 1")
        sizer.Add(t,1,wx.EXPAND,0)      

class Page2 (wx.Panel):
    def __init__(self,parent):
        wx.Panel.__init__(self, parent=parent)
        sizer = wx.BoxSizer(wx.VERTICAL)
        t=wx.StaticText(self,-1,"THIS IS PAGE 2")
        sizer.Add(t,1,wx.EXPAND,0)

if __name__ == '__main__':
    app = wx.App()
    frm = MainPage(None)
    frm.Centre()
    frm.Show()
    app.MainLoop()