Path: utzoo!attcan!uunet!dino!ux1.cso.uiuc.edu!tank!gft_robert@gsbacd.uchicago.edu
From: gft_robert@gsbacd.uchicago.edu
Newsgroups: comp.sys.mac.hypercard
Subject: Under lock and key: can't get screen to unlock in middle of handler
Message-ID: <8062@tank.uchicago.edu>
Date: 14 Mar 90 20:03:42 GMT
Sender: news@tank.uchicago.edu
Organization: University of Chicago Graduate School of Business
Lines: 53

I've to a handler in one stack that will need to process a lot of cards (ca.
1000).  I thought it might be nice to provide one of those little "bar
graphs" on screen which lets the user know how much has been done.

The problem is: in my handler I'm going to each of the cards in question.  In
the interests of speed and appearance I lock the screen on entering the
handler.  So in my bar-graph-handler, I go back to the card I started on,
unlock the screen, fill in the bar graph, lock the screen again, and go back
where I was.

Or so I thought.  The screen won't unlock for me and my graph doesn't get
drawn.  Is there some trick to this?  Can you lock and unlock the screen from
within a handler?

Here is pseudo-code for my handlers:

on DoBigThing
 put id of this cd into origID
 lock screen
 push cd
 repeat with n=1 to BigNum
  go to cd n
  do lots of stuff (writing to file, etc.)
  DoMyGraph n,BigNum,origID
 end repeat
 pop cd
end DoBigThing

on DoMyGraph nowValue,maxValue,origID
 push cd
 go to origID
 unlock screen
 draw my graph using proportion of nowValue to maxValue
 lock screen
 pop cd
end DoMyGraph


This doesn't work even if I put the lock/unlock combo in the outer handler,
surrounding the call to DoMyGraph.

Any clues?  Help much appreciated!

Robert



 
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= gft_robert@gsbacd.uchicago.edu * generic disclaimer: * "It's more fun to =
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