[plt-scheme] GUI Development Approach

Hi all,

I'm not used to development of GUI applications but from what I've
seen from GTK apps (generated usually by Glade) and MrEd apps, code
gets a mess rapidly since all widgets get stuck into the same file
when created due to the fact that they interact with one another. A
button click updates a list box. The list box updates some fields. The
menu bar... etc, etc, etc...

Is there a structured approach to writing a GUI without having to
define all widgets in a module.
I tried to define each GUI part as an object. Initially I had a
dependency graph and I made sure all widgets which generated a
dependency cycle (changed each other) were within the same module. And
the initial implementation started ok. With the need to add features,
I started to need to change this button and that label and that...
that were in diferent models. Now I'm stuck in the middle of cyclic
module dependencies... :-|

Any hints, tips, or reference papers would be _greatly_ appreciated.

Cheers,
--
Paulo Jorge Matos - pocm at sat inesc-id pt
Web: http://sat.inesc-id.pt/~pocm
Computer and Software Engineering
INESC-ID - SAT Group