From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Thread: 103376,26a21b9e317dc639
X-Google-NewGroupId: yes
X-Google-Attributes: gida07f3367d7,domainid0,public,usenet
X-Google-Language: ENGLISH,ASCII-7-bit
Received: by 10.66.81.200 with SMTP id c8mr3736045pay.1.1353410183057;
        Tue, 20 Nov 2012 03:16:23 -0800 (PST)
Path: 
 s9ni1536pbb.0!nntp.google.com!news.glorb.com!us.feeder.erje.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!mx04.eternal-september.org!.POSTED!not-for-mail
From: Brian Drummond <brian@shapes.demon.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: Access type to member procedure of instance (Object Oriented
 programming in Ada)
Date: Tue, 20 Nov 2012 11:16:22 +0000 (UTC)
Organization: A noiseless patient Spider
Message-ID: <k8foq6$1hv$2@dont-email.me>
References: <9b0bcb37-8ae3-440f-af4f-a796702e4250@googlegroups.com>
	<8906e1e3-3b18-4b37-ac46-3857db47cea4@googlegroups.com>
Mime-Version: 1.0
Injection-Date: Tue, 20 Nov 2012 11:16:22 +0000 (UTC)
Injection-Info: mx04.eternal-september.org;
 posting-host="dfff62e1e537b55df42008571c03e0fe";
	logging-data="1599"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX19ZVYwQtbIefOjEXeHaSPJq3mS+N1Xnq0E="
User-Agent: Pan/0.139 (Sexual Chocolate; GIT bf56508
	git://git.gnome.org/pan2)
Cancel-Lock: sha1:TK90ItesGKi5oS8BrQAOtjlyCeg=
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Date: 2012-11-20T11:16:22+00:00
List-Id: <comp.lang.ada>

On Mon, 19 Nov 2012 12:22:21 -0800, ake.ragnar.dahlgren wrote:

> On Monday, November 19, 2012 10:59:42 AM UTC+1, ake.ragna...@gmail.com
> wrote:

>> This problem has it's origin in the implementation of the MVC pattern
>> for a GtkAda application. Consider the following:
...
> Additional information if needed: The spec. of the Register_Handler
> procedure in the Gtkada.Builder package is declared as:
> 
> procedure Register_Handler
>   (Builder      : access Gtkada_Builder_Record'Class;
>    Handler_Name : String;
>    Handler      : Builder_Handler);

Okay, this is looking familiar...

A previous post of mine linked at the bottom of the ada.dk tutorial 
contains the comment :

-- Having only Gtkada_Builder_Record'Class and GObject_Record'Class
-- seems restrictive. I failed to find any way to register and use 
-- the following:
--    procedure Destroy(Object : access Gtk_Widget_Record'Class);
-- eventually resorting to Gtk.Builder.Get_Widget in the procedure body.
-- I must be missing something here...

To expand on that; clearly everything is a subclass of GObject_Record, 
and therefore the intent must be that anything more complex like your 
On_Quit example be registered as an Object_Handler not a Builder_Handler.

--   type Builder_Handler is access procedure
--     (Builder : access Gtkada_Builder_Record'Class);
--   type Object_Handler is access procedure
--     (User_Data : access GObject_Record'Class);

The remaining question would be ... how?

It might be worth putting your On_Quit handler into the tutorial example, 
and asking "How do I register this as an Object_Handler?" on the GtkAda 
mailing list.

- Brian