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From: dedreb@arco.com (Richard Beecher)
Newsgroups: comp.sys.mac.programmer
Subject: Re: GrowWindow Woes, Help Please
Message-ID: <1991Apr22.164037.17692@Arco.COM>
Date: 22 Apr 91 16:40:37 GMT
References: <9190.2810258e@jetson.uh.edu>
Sender: news@Arco.COM
Distribution: usa
Organization: Arco Alaska
Lines: 48

In article <9190.2810258e@jetson.uh.edu> englhq@jetson.uh.edu writes:
>I'm working through the window techniques in Huxham, Burnard and Takatsuka's
>USING THE MACINTOSH TOOLBOX WITH C, and I'm stuck at the GrowWindow function.
>The code goes like this:
>
>case inGrow:
>     newSize=GrowWindow(whichWindow,theEvent.where,&limitRect);
>     SizeWindow(whichWindow, LoWord(newSize),HiWord(newSize),0xff);
>     contRgnHnd=theWindowRec.contRgn;
>     tempRect=(*contRgnHnd)->rgnBBox;
>     EraseRect(&tempRect);
>     DrawGrowIcon(theWindow);
>     break; 
>
>What happens is, the outline of the scroll bars and size box remain in the
>middle of the window. i.e. It seems that the EraseRect isn't doing what I
>think it's supposed to.
>

Can't say that I know exactly what is happening here, but I wonder if a simpler
approach would fix the problem.  In the above code, you are referencing
whichWindow, theWindowRec, and theWindow.  How about trying the following code?

case inGrow:
     newSize=GrowWindow(whichWindow,theEvent.where,&limitRect);
     EraseRect(&whichWindow->portRect);
     SizeWindow(whichWindow, LoWord(newSize),HiWord(newSize),0xff);
     DrawGrowIcon(whichWindow);
     break;

Here, I only reference whichWindow.  Also, for aesthetic reasons, I EraseRect
before resizing the window.  I think Apple also recommends this in the user
interface guidelines (IM-1 section on Window Manager?).

Erasing the window's portRect should accomplish the same thing as erasing its
content region.  Ah hah!  I might be on to something hereQthe window's content
region is expressed in global coordinates...its portRect is expressed in local
coordinates.  This might be the source of your problem.  Essentially, you are
erasing a rectangle that is outside your window's clipRgn.  So if you want to
stick with your original code, converting tempRect to local coordinates might
fix your problem.

Good luck!

---------------
Richard Beecher
dedreb@arco.com
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