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From: doron@mobydick.leis.bellcore.com (Doron Shalmon)
Newsgroups: comp.windows.interviews
Subject: Re: GetCanvas returns NULL
Message-ID: <1991May14.052613.29659@bellcore.bellcore.com>
Date: 14 May 91 05:26:13 GMT
Article-I.D.: bellcore.1991May14.052613.29659
References: <9105120300.AA29103@shiva.trl.OZ.AU> <1991May13.161932.28060@fido.wpd.sgi.com>
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Reply-To: doron@mobydick.leis.bellcore.com (Doron Shalmon)
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Organization: Bellcore, Piscataway, NJ
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In article <1991May13.161932.28060@fido.wpd.sgi.com> you write:
|> Please explain in what context you are calling redraw explicitly.
|> If you call redraw when the window is unmapped, for example,
|> the canvas will be nil.

Is there some point in the life of an interactor when it is guaranteed
to be mapped?  What I'm looking for is some member function in which
I can be guaranteed that the canvas is not nil (much the same way as
you *know* that the interactor knows about its parents and the world
in Reconfig).

Specifically, I have a damage object that needs to know the canvas
of a graphic block, and I'd like to have the graphic block take care
of this when it gets mapped (rather than do some explicit Set call
after I insert the graphic block into the world).

Thanks.

===========================================================================
                               Doron Shalmon
           Bellcore -- Network Planning and Distribution Systems
                  Internet:  doron@yogi.leis.bellcore.com
                      UUCP:  ...!bellcore!yogi!doron

    "All opinions expressed are mine, and do not necessarily represent
      those of my employer, Bell Communications Research (Bellcore)"