Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!spool.mu.edu!uunet!timbuk!marc
From: marc@sequoia.cray.com (Marc Bouron)
Newsgroups: comp.sys.atari.st.tech
Subject: Re: saving screen in a GEM app.
Keywords: save screen, GEM application, form_dial
Message-ID: <115241.1926@timbuk.cray.com>
Date: 24 Apr 91 18:03:53 GMT
References: <1991Apr24.012040.22627@netcom.COM>
Reply-To: marc@sequoia.cray.com (Marc Bouron)
Organization: Cray Research, Inc.
Lines: 39


In article <1991Apr24.012040.22627@netcom.COM>, rcb@netcom.COM (Roy Bixler) writes:
|> 
|> I am writing a GEM application based on a dialog box which
|> occasionally has another dialog box written over it.  When this
|> 'pop-up' dialog box is done and I have called form_dial() the second
|> time, instead of the original dialog box being restored, the desktop
|> background is restored.  Obviously, that doesn't 'cut it'.  Is there a
|> way for me to save the background and restore it when I'm done with
|> the 'pop-up' dialog?
|> 
|> It looks like the problem is that GEM is not aware that my original
|> dialog box is the background.  How do I notify GEM that the background
|> is not the original desktop?  I've thought about doing a 'wind_set(0,
|> WF_NEWDESK, ...)' but, if I do that, how would I get the original
|> desktop back when my application is done?
|> 
|> Maybe insanity is the best answer.  Any suggestions otherwise?

You should write your application so that it uses AES - i.e. use evnt_mesag()
or envt_multi() calls.  This way, when you free up a patch of screen where your
dialog used to be with the form_dial() call, the AES will send you a message to
tell you what area of the screen needs redrawing.  (It's up to you to do the
redrawing - if your dialog is an object tree, this is no problem.)

If all this is news to you, then I would suggest Tim Oren's ProGEM series of
articles as a damn decent way to teach you about these things.  Certainly an
improvement on my ramblings...

[M][a][r][c]


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