Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!mcsun!unido!tub!db0tui11!MUHRTH
From: MUHRTH@DB0TUI11.BITNET (Thomas Muhr)
Newsgroups: comp.lang.smalltalk
Subject: RE: SmallTalk V/286 TopPanes
Message-ID: <483@DB0TUI11.BITNET>
Date: 4 Jan 90 14:15:07 GMT
Reply-To: MUHRTH@DB0TUI11.BITNET (Thomas Muhr)
Organization: TU Berlin
Lines: 28
Disclaimer: Author bears full responsibility for contents of this article

This is a response to David Yon's message, where he wonders about image-
filling panes left in the system without an appearant handle to get rid
of these. I had these kind of problems too, and with a little help from
the very knowledgeable people here got finally (hopefully) rid of them.
The problem is that every time you open a view on a model the dependencies
between them is recorded in a classvariable of Object, 'Dependents'.
Upon closing a view these dependencies are (very radically!) removed from
the Dependents-dictionary. But, if the dispatcher didn't get the chance of
performing a correct close, which can have lots of reasons (we all produce
erronous code sometimes...), the dependencies stay in the list.
You should do the following: Dependents inspect. Than remove all models,
which you are sure are NOT the ones which are needed (Transcripts TopDispatcher
 etc.) This should help.
Another way of getting rid of instances, which is more harmful, because you
can 'saw the branch you are sitting on' (I don't know, if this is a valid
english idiom...) is the following:
! Behaviour methods!
eraseAllInstances
self allInstances do:[:inst| inst become: String new].
You can now erase ALL instances of a class by: CLASSxyz eraseAllInstances.
BUT, TextPane eraseAllInstances will give you a hard time......
Good luck, Thomas

-------
Thomas Muhr, Technical University of Berlin, BITNET: muhrth@db0tui11
   Project ATLAS - Computer Based Tools for Qualitative Research
         "Computers, like every technology, are a vehicle
      for the transformation of tradition." (WINOGRAD/FLORES)