Notebook image bug on win32, working on GNU/Linux and Mac OSX

[Frank Aune]

Hello,

This is probably far-fetched without a minimal runable example, but  
here goes ... I have a fairly large program, which lets the users  
enable and disable notebook tabs dynamically in any order they see  
fit. (Think of tabbed browsing using a web browser - The first  
notebook tab can never be disabled though. It is always present) The  
notebook and imagelist is created like this in the application:

self.il = wx.ImageList(32,32)
self.il.Add(wx.Bitmap('img%simg1.png' % os.sep, wx.BITMAP_TYPE_PNG))
self.nb = xrc.XRCCTRL(self.frame, 'main_notebook')
self.nb.SetImageList(self.il)
self.nb.SetPageImage(0,0) # (page, image)

Then I have some additional tabs which hooks themselves up during  
launch. Each tab is defined inside a python class, so they get the  
reference to the main app in their constructor, here called parent:

# self.panel is this class' notebook panel
# self.title is the title for this tab
tabOrder = self.parent.nb.GetPageCount() # Get the first available  
tab index
self.parent.il.Add(wx.Bitmap('img%simgname.png' % os.sep,  
wx.BITMAP_TYPE_PNG) # Add my image to imagelist
self.parent.nb.InsertPage(tabOrder, self.panel, self.title) # Add  
myself to the notebook
self.parent.nb.SetPageImage(tabOrder, tabOrder) # Set my image from  
imagelist
self.parent.nb.Refresh() # fix win32 redraw bug?

For removing tabs, I use the following code, also present inside the  
python class defining the tab:

for i in range(self.parent.nb.GetPageCount()):
     if self.parent.nb.GetPageText(i) == self.title:
         self.parent.il.Remove(i)
         self.parent.nb.DeletePage(i)
         self.parent.nb.Refresh() # fix win32 redraw bug

Both code blocks above exist in a tab superclass which each tab class  
inherrit.

This is where it gets interesting. The above works 100% on both GNU/ 
Linux Kubuntu Feisty Fawn using wx-2.8 and python2.5 from the default  
repositories, and Mac OSX 10.4 using python2.5 and the latest wx as  
of this date.

But on Win32 otoh, using also python2.5 and the latest wx, I get very  
strange behavior. Most of the time the second tab shows up without an  
image, while the rest have images. But adding and removing tabs in  
random order will eventually trigger a new effect where random tabs  
might loose their image also. And the effect is "contagious" because  
if you keep adding/removing tabs in random order, they will all but  
the first one eventually end up without an image.

(On an interesting (but probably unrelated) note: If I delete the  
page from the notebook before removing the image from the imagelist  
(that is; the reverse of what I do above in the last code section),  
the application will misbehave on all plattforms in another way: Then  
the wrong image will be mapped to different tabs when removing tabs etc)

Could anyone theorize or think out aloud what might be making these  
rather strange effects Im experiencing on Win32, based on the  
provided info?

Best regards,
Frank