Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!apple!stadler
From: stadler@Apple.COM (Andy Stadler)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: OptionKey and ShiftKey STUCK down
Message-ID: <49891@apple.Apple.COM>
Date: 5 Mar 91 19:21:41 GMT
References: <8835@castle.ed.ac.uk>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 42

In article <8835@castle.ed.ac.uk> helper@castle.ed.ac.uk (A Wilson) writes:

>I need help with a hypercard problem.  I have written a
>stack which tests students' responses to shapes on the
>screen.  If the shape is longer on the left, they press the
>Option key, if it is to the right they press the Shift key.

>The tests work fine, but every so often, it seems that
>hyprercard thinks that one or both of these keys are STUCK
>down and as a result the stack assumes that the student has
>answered by pressing the key which is stuck down.

Most likely, the repeated pressing of the shift key is activating the "sticky
keys" feature.  Sticky Keys is a part of the Universal Access package, a set
of utilities which facilitate use of the computer by people with reduced
physical capabilities.  Sticky Keys is specifically designed to allow use of
the keyboard by a person who can only press one key at a time (which would
preclude use of shift, option, or command).  It's activated by (does this
sound familiar?) pressing the shift key five times in a row without moving
the mouse or pressing any other keys.

Once activated, sticky keys works like this:  Each time you press a modifier
key, it "sticks" so the next key will be modified.  And if you press the 
modifier twice, it "locks" so an entire sequence of modified keys can be
typed.

To determine if this is what's messing your system up, watch the upper right-
hand corner of the screen while people are using your program.  If you see a
little icon appear, that's sticky keys at work.

How you can fix it:  There are a number of things you could do, including...
1.  Remove the "Easy Access" file from your system folder.
2.  Modify your test to not use the shift key.  Use Option or Command instead.
3.  Modify your test to require mouse movement or use of other keys.  Remember,
    it's five presses of the shift key with NO OTHER keyboard or mouse
    activity.

Hope this helps.

Andy Stadler
HyperCard IIGS Team
Apple Computer, Inc.