[Urwid] beginner help

[Pedro Jorge Caridade]

Hello to all
I'm starting to use urwid, although not totally free of errors, 
problems, etc.... Beginner's things!

I going through Rebecca's example rbreu_filechooser.py to learn dynamic 
ListBox. By trial-and-error I manage to understand the example (also 
very well documented) but I have one question that I cannot solve in 
trying to implement in my application. If I have two columns like 
Rebecca's example and I want that only one of them have the focus? I'm 
using a SimpleListWalker and a ListBox to construct the two columns.

Thank's for any help
Pedro
_ <http://excess.org/urwid/browser/contrib/trunk/rbreu_filechooser.py>_