Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!stadler
From: stadler@Apple.COM (Andy Stadler)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: Simulating arrays (Of tickboxes)
Message-ID: <52552@apple.Apple.COM>
Date: 7 May 91 17:38:36 GMT
References: <9105070137.AA07503@cs.utexas.edu>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 25

In article <9105070137.AA07503@cs.utexas.edu> PCT501@saturn.ukc.ac.uk writes:

>What I really *want* is a background checkbox whose high-light is stored
>on a per card basis, much like the contents of a text-field.

Beginning with HyperCard 2.0, there is a new background button property called
"shared hilite".  The default is "on", which emulates the behavior of bkgnd
buttons in HyperCard 1.2.5.  But if you create a bkgnd button, and turn
shared hilite "off", you will get a unique hilite state for each card.  This
is -exactly- what you are looking for.

Implementation note:  If you consider text (the "data" of a field) and hilites
(the "data" of a button) as conceptually identical, you can see that the
system of shared/unshared hilites is quite similar to the concept of shared/
unshared text, which was also added in 2.0.  In fact, many, many people were
asking for "shared bkgnd text" but when we implemented it, we discovered that
it was just a easy to implement it more generally and thus give new capa-
bilities to buttons as well.  The only real difference is the defaults, which
are set "true" for buttons and "false" for fields - to emulate 1.2.5.

[Just for the record, we invented it for HyperCard IIGS and kindly shared our
source code with the Mac 2.0 team.... :)  ]

Andy Stadler
Apple Computer, Inc.