Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!hoptoad!tim
From: tim@hoptoad.uucp (Tim Maroney)
Newsgroups: comp.sys.mac.programmer
Subject: Re: A couple of problems a beginner is having. . .
Message-ID: <7842@hoptoad.uucp>
Date: 4 Jul 89 01:41:25 GMT
References: <42687@tiger.oxy.edu> <29911@ucbvax.BERKELEY.EDU>
Reply-To: tim@hoptoad.UUCP (Tim Maroney)
Organization: Eclectic Software, San Francisco
Lines: 30

In article <42687@tiger.oxy.edu> adams.e@oxy.edu (Erik Adams) writes:
>     1.)  If I move an application window on top of a system
>window (the control panel, for example), and then move it away,
>the system window is _not_ updated. 

In article <29911@ucbvax.BERKELEY.EDU> oster@dewey.soe.berkeley.edu.UUCP
(David Phillip Oster) writes:
>It is clear that you forgot the "inSysWindow" case.

Uh, David, how could leaving a clause out of mouse down event handling
have anything to do with update events?  SystemClick definitely is not
in charge of system updates....

My idea was that he was using GetOSEvent, which wouldn't call
SystemEvent.  However, another possibility I realized later was that he
might be passing an invalid event mask, one without the updateMask bit
set.  This is similar to the error you pointed out recently in that
flawed security scheme.  A beginner could easily mistake the event
type codes for the event mask bit values.  This would not only prevent
the application from receiving update events, it would prevents them
being passed to SystemEvent from inside GetNextEvent.
-- 
Tim Maroney, Mac Software Consultant, sun!hoptoad!tim, tim@toad.com
Postal: 424 Tehama, SF CA 94103; Phone: (415) 495-2934

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