PyGTK "assertion GTK_IS_WINDOW failed

I'm trying to build a web browser using PyGTK and PyWebKit

However, I'm pretty sure my question only concerns PyGTK

I have a custom gtk.Notebook class, with an "add tab" button as the last tab. When I click it, it gives me the error

/home/ruiq开发者_如何学JAVAimao/workspace/PyBrowser/src/browser/__init__.py:161: GtkWarning: IA__gdk_window_get_cursor: assertion `GDK_IS_WINDOW (window)' failed  gtk.main()

twice.

And then, my new tab won't show up.

I have no idea what is going on, so here is my whole code

If any of you could help me, that would be great!

Thanks!

[EDIT]: Just found out that the problem lies in the w.show_all() line What could this mean?

This question has been sitting in "unanswered" for months, without any answer. However, the problem was indeed solved (see comments). Thus, as a service to get this question OUT of "unanswered", I'll restate the apparent answer. If anyone else can top me, pleeeeeeeease do. :)

You forgot to show the new tab.

Thank you, and goodnight. :)