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From: tenny@ootool.dec.com (Dave Tenny)
Newsgroups: comp.sys.next
Subject: View invalidation, scaling, [window display] vs. [view display]
Message-ID: <1991May20.163623.10272@engage.pko.dec.com>
Date: 20 May 91 16:32:52 GMT
Sender: newsdaemon@engage.pko.dec.com (USENET News Daemon)
Organization: Digital Equipment Corporation
Lines: 30


Perhaps someone can answer the following question.

I have a view which I am drawing in using PSxxxx functions.
It is the docview of a scrollview.  

When I scale the docview in response to hitting a "magnify" button, say:

[docview scale :1.2 :1.2] ; 

then

[docview display] ;

the OLD contents of the docview are displayed, unscaled, as well as the 
new, scaled contents.

However, if I do a

[window display] instead for the app's main window (which contains the 
scrollview/docview), then everything works fine. However, this visibly
redraws the whole window, and is unpleasant to watch.  

What is the proper way to redraw the docview?  

I tried all kinds of things including
displaying various superviews, setting notify flags, etc..  Only
displaying the window caused the desired display of the docview.

Dave