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Newsgroups: comp.lang.ada
Date: Thu, 28 Apr 2016 00:49:47 -0700 (PDT)
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Subject: Re: Where do I get my Cairo context from (in GTK3)?
From: briot.emmanuel@gmail.com
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Xref: news.eternal-september.org comp.lang.ada:30312
Date: 2016-04-28T00:49:47-07:00
List-Id: <comp.lang.ada>

> I used another approach. Instead of asking the user to draw anything, I 
> let him create an object, e.g. a line, which will knows how to draw 
> itself. The object is put into a list of objects.

I use a similar approach indeed, and ended up creating GtkAda.Canvas_View
with exactly that design ( and a model-view-controller approach too). This
might be what the original poster was looking for.