[plt-scheme] MrEd: how can I _cleanly_ keep the states of various widgets in sync?

From: Matt Jadud (jadudm at gmail.com)
Date: Fri Nov 30 11:01:19 EST 2007

Hi Eric,

Is there a reason that MVC doesn't provide the necessary abstraction?
That is, your GUI has a state (model), and your GUI widgets are
observers of that model (views) who need to be updated when it
changes? Or, is the overhead of actually having to express the MVC
"unclean"? (FWIW, having the ability to easily register listeners as
per Matthew's comment could be quite nice, all of that said.)

On Nov 30, 2007 9:44 AM, Ivanyi Peter <pivanyi at freemail.hu> wrote:
> You can also try the MrEd Designer which uses "direct call"
> to achieve the interaction between widgets.
> (When using MrEd Designer, select the Windows->Call graph Frames
> and in that window you can do the editing. The program will write
> the code for you automatically.)

And Peter, I wanted to ask something about MrEd Designer: while it is
true that Designer will "write the code automatically," I find that
the way it writes the code makes it very hard to modularize and work
into a larger program. Would you, as the shepherd of MrEd Designer, be
willing to entertain some discussion about to improve the output of
Designer so that it can more easily be integrated into a larger
application? (Both I and my students discovered this term that it was
easier to simply write the GUI by hand than use MrEd Designer, because
the code it output was not ready to be incorporated as a module in a
larger app.) I once applied a hack like this to the code (a good three
or four year ago), but could look at providing a reasonable patch


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