Date: Thu, 3 Jul 2003 15:42:23 +0100
To: lablgtk at kaba.or.jp
Subject: containers & subclasses of widgets
Message-ID: <20030703144222.GA15588 at redhat.com>
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From: Richard Jones <rich at annexia.org>


I have another question regarding containers. I'm using a 2x2 table,
with each cell of the table populated with a vbox. A table is-a
container, so I can use the table#children method to get a list of the
children (presumably - I haven't actually tried this, or seen if they
come out in a useful order).

The problem is that table#children gives me a list of widgets. How can
I usefully convert these to vboxes without doing a forbidden downcast?
(My first thought was that container ought to be a polymorphic class,
but of course that wouldn't allow you to store different types of
widgets in a single container.)

I guess this comes down to the strange type system used by LablGtk. Is
this explained in comprehensible terms anywhere?

Thanks for your help,

Rich.

-- 
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