Program Structure

[frankc srv net]

I am having trouble understanding the structure of programming a GTK+
app. My biggest hangup is how do I modify a widget that is nested in a
window several levels down?  I looked at mapping to it by name or
creating a master structure containing all the widget pointers.  Neither
of these look very practical.  Another method I thought of was creating
a callback that responds to a signal manufactured by another widget.
This last I am not sure how to approach, but I am hoping I can send data
to the widget that responds to the signal.  This problem probably has a
simpler solution.  I am new to programming this way as opposed to a
linear program. I am used to having access to all my data all the time.
I would like to keep my apps object oriented, but I am not understanding
how to make widgets talk to each other easily without destroying the OO
barriers.

Thanks,
Frank