Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-ncis!helios.ee.lbl.gov!pasteur!ucbvax!hoptoad!tim
From: tim@hoptoad.uucp (Tim Maroney)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Updating dialogs
Message-ID: <6179@hoptoad.uucp>
Date: 6 Jan 89 09:58:58 GMT
References: <373@lclark.UUCP>
Reply-To: tim@hoptoad.UUCP (Tim Maroney)
Organization: Eclectic Software, San Francisco
Lines: 21

In article <373@lclark.UUCP> dan@lclark.UUCP (Dan Revel) writes:
>What's the best way to update a non-modal dialog after changing one of
>its dialog items?  Here's my problem: I want to display differing icons
>in response to user radio button selections, right now I call DrawDialog(...)
>to redraw the whole window but that causes everything to flicker and I would
>rather just redraw the icon I have changed.  I tried just using InvalRect on
>the rect returned by GetDItem but to no update event is generated...

You also need to make sure that the current GrafPort at the time of the
InvalRect is the dialog GrafPort.  If you do this, an update event will
be returned on the dialog by GetNextEvent, and when you call DialogSelect
the item will be redrawn.  My guess is you just forget to set the GrafPort
before doing the InvalRect.  It would also be a good idea to do an
EraseRect before or after doing the InvalRect, or you may find your
new icon superimposed over the old one (or maybe not, but it shouldn't
hurt to be safe).
-- 
Tim Maroney, Consultant, Eclectic Software, sun!hoptoad!tim
"There's a real world out there, with real people.  Go out and play there for
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