Re: wanted: expertise with Gtkada.Canvas_View in gtkada 17.0

[mario.blunk.gplus@gmail.com]

On Friday, November 29, 2019 at 1:48:07 PM UTC+1, briot....@gmail.com wrote:
> > does anyone here have expertise with the package Gtkada.Canvas_View ? 
> 
> I wrote it at the time, but I haven't used GtkAda for three years now so
> I am a little rusty on the subject. You could still try sending your actual
> question, maybe other people can help.

I'm still playing with my demo at https://github.com/Blunk-electronic/ada_training/tree/master/src/gtkada_8 . The requires library units are in
https://github.com/Blunk-electronic/ada_training/tree/master/src/lib .

In the package spec Gtkada.Canvas_View you say that in order to customize the canvas background, the procedure draw_internal should be overridden (line 53). If I'm correct, this implies extending the type canvas_view_record and overriding draw_internal of the derived type. This is what I did in my demo in file gtkada-canvas_view-canvas_test.ads . The derived type is type_view. Right below is the overriding of draw_internal. The actual overriding takes place in gtkada-canvas_view-canvas_test.adb .
 Here I'm stuck.  So my first question: Do I need the pointer type_view_ptr that accesses the type_view ?

Thanks