Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!psuvax1!julius.cs.uiuc.edu!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink!a347
From: John_Miller@mindlink.UUCP (John Miller)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: Question about protocol for trapping menu items.
Message-ID: <4621@mindlink.UUCP>
Date: 29 Jan 91 14:42:26 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 63



> Ok, but what if you're the top stack in the stacksInUse and
> there's another stack below you that also has a doMenu > handler that closes
its windows?  If you send the command
> straight to HyperCard the other stacks never get it.  I've
> been wrestling with this general problem (passing on a message
> so other stacks get it but still doing something after the
> message is "finished") and I haven't come up with a good solution.
> I've resorted to setting a global flag and checking it in an idle
> handler, but I don't really like doing it that way.  Would it be
> better to find my stack's place in the stacksInUse list and send
> the message on to the following stack?  Any suggestions?

A solution is to use a global variable, but it doesn't have to
be within the idle handler.  It can all be handled within
the doMenu menu handler.  The trick is to deliberately
cause one level of recursion.  This code relies on the
fact that a global variable that is declared but not
initialized is considered to be empty:  a very useful
feature of HyperTalk.

on doMenu theItem
  -- This global is only declared in this handler:  nowhere else
  global amRecursing
  if amRecursing is not empty then
    play flute   -- Remove from production code :)
    pass doMenu
  else
    if theItem is "Compact Stack" then
      close window "MyPalette"
      put true into amRecursing -- Any non-empty value would do
      send "doMenu Compact Stack" to me -- causes recursion
      play boing  -- Remove from production code :)
      put empty into amRecursing
      palette "MyPalette", "345,80"
    else pass doMenu
  end if
end doMenu


Actually, is the warning about hiding palettes valid?
HyperCard doesn't complain when I try to compact
a stack with a custom palette.  It does complain
when I try to compact a stack X that contains a windoid
that is controlled by an XCMD located in stack X.
Presumably, the Palette XCMD "lets go" of the PLTE and
PICT resources once it has created the window. (Yes? No?)

An unrelated palette question:  is the format of the
PLTE resource documented or do I have to reverse-engineer
it.  I was thinking of creating some XCMDs that would allow
customization:  "If you don't like the default look of
the windoid, create your own palette using the Palette
Maker.  Your palette should have four buttons:  the first
will invoke ... the second will invoke ...."

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John Miller                         (604) 433-1795
Symplex Systems                     AppleLink (rarely)  CDA0461
Burnaby, British Columbia           Fax: (604) 430-8516
Canada                              usenet:  john_miller@mindlink.uucp
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