Path: utzoo!attcan!uunet!cbmvax!vu-vlsi!swatsun!jackiw
From: jackiw@cs.swarthmore.edu (Nick Jackiw)
Newsgroups: comp.sys.mac.programmer
Subject: Re: MultiFinder & Modal Dialogs
Message-ID: <2311@ilium.cs.swarthmore.edu>
Date: 16 Jan 89 18:10:58 GMT
References: <2299@ilium.cs.swarthmore.edu> <1678@helios.ee.lbl.gov>
Reply-To: jackiw@ilium.UUCP (Nick Jackiw)
Organization: Visual Geometry Project, Swarthmore College, PA
Lines: 33

In article <1678@helios.ee.lbl.gov> beard@ux1.lbl.gov (Patrick C Beard) writes:
> In article <2299@ilium.cs.swarthmore.edu> jackiw@swatsun.UUCP () writes:
> >In article <482@pyuxf.UUCP> asg@pyuxf.UUCP (alan geller) writes:
> >> 	WHY can't layer switches happen when a modal dialog is displayed?
> >THE WHOLE PROBLEM:
> >The modal app CAN'T PROCESS ITS UPDATES...
> Untrue.  You are forgetting the parameters that are passed to ModalDialog:
> 	pascal void filterProc();
> 	short int itemHit;
> 	ModalDialog(filterProc, &itemHit);
>                 ^^^^^^^^^^
> Then from within your filterProc you just call ProcessEvents() when
> appropriate.
> Patrick Beard

You're right, but what I wrote IS true.  Of course it's possible to code an
app so that MF can switch out from modal situations.  Elsewhere in my article
I mentioned exactly that possibility.  The vast majority of apps written in
Multifinder times and ALL apps written before it, however, are NOT going to
implement a filterProc to process updates for non-modal windows. Before 
Multifinder, this was considered an impossible occurence.  We were talking
about why MFinder's backward-compatibility enforces total modality, not about
what tricks wonder-boy can teach wonder-app with total retrospective knowledge
of the inner workings of an elaborate and elegant multiprocessing kludge. 

Follow before ya flame.


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