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From: bjoern@drdhh.hanse.de (Bjoern Kriews)
Newsgroups: comp.sys.atari.st.tech
Subject: Re: saving screen in a GEM app.
Message-ID: <2972.04.91@drdhh.hanse.de>
Date: 29 Apr 91 11:29:40 GMT
References: <115241.1926@timbuk.cray.com>
Organization: Digital Island
Lines: 65

From article <115241.1926@timbuk.cray.com>, by marc@sequoia.cray.com (Marc Bouron):
> |> 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?

GEM's form_dial is just a way to tell the screen manager that it has
to force the application to redraw it's screen.

Since dialogs are not windows, you have to use code like this:

form_center(dial1,...);
form_center(popup,...);

redraw=TRUE;
form_dial(FMD_START,dial1....);

do{
		if(redraw)
			{
				objc_draw(dial1,....);
				redraw=FALSE;
			}	

		ex=form_do(dial1...) & 0x7fff;

		switch(ex)
			{
				case CALLPOP:
					form_dial(FMD_START,popup...); /* not needed if popup is < dial */
					objc_draw(popup,....);
					form_do(popup,....);
					form_dial(FMD_FINISH,popup....); /* "" */
					redraw=TRUE;
				break;

				case ANYTHING:
					form_alert(1,"[0][What you want][XXX]");
				break;
			}

} while(ex != EXDIAL1);

form_dial(FMD_FINISH,dial1....);


I hacked this from memory because my sources are on backup for the moment,
but that's the way my applications handle it.


Notes:
Alerts restore there bg automatically.
I discovered that form_dial(START/FINISH) may be used out of specific order
but I never found this being official, be aware.

Hope that helps, 
	Bjoern
	

---
bjoern@drdhh.hanse.de = Bjoern Kriews / Stormsweg 6 / 2000 Hamburg 76 / FRG
"gaaga mahwe Bjoern urgl ufzae Turbo-C bnub"     (J. Willamowius)