Fixing some model incompatibilities

In theory, we should be able to swap in a new model with the same method calls and our application object will just work, but this isn't quite the case. There are a few small fixes we need to make to get Application working with our new model.

Get Python GUI Programming with Tkinter now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.