Undoing

[fuegox at mac.com]

On Friday, January 11, 2002, at 07:33 PM, David Epstein wrote:

> Has anybody found a good way to make the standard "Undo" command apply 
> to
> specific scripted routines?
>
> It seems pretty straightforward to store the "status quo ante" 
> situation,
> and catch an undo command that would put things back.  The problem is 
> how to
> make that option expire as soon as it should.  Certainly I'd want the
> undo-this-routine option to disappear if the user has since done 
> something
> that Metacard itself makes undoable (like typing in a field); or if the 
> user
> has gone to some other card.  Is there a reasonable list of system 
> messages
> that might be intercepted and taken as signals to "clear the custom undo
> buffer"?  Is there some way to detect when MC's own undo option (for 
> its own
> undoable routines) has become (or whether it remains) available?
>
> Thanks for any thoughts.
>
> David Epstein
>

Darn good question.  I too have wondered what would be the best way to 
implement this vary standard feature.  The problem can be daunting if 
you have an app that is complex and needs to support that feature 
everywhere.  Sorry for I do not know the answer to your question.  But I 
will be reading to see if someone out there does.

-Mark Talluto