Re: [orca-list] Geany, SciTE and other Scintilla based applications

[Mike Gorse <mgorse alum wpi edu>]

Hi Mike,

Unfortunately, we don't really have a good tutorial for building custom 
atk classes (I thought there was one around somewhere, but now I can't 
find it, and it would be outdated anyhow). My suggestion would be to look 
through gtk's accessibility code (in gtk/a11y for gtk 3) and look at the 
atk documentation as a reference:

https://developer.gnome.org/atk/unstable/

For the stable gtk+ sources: 
ftp://ftp.gnome.org/pub/gnome/sources/gtk+/3.12

If you only need to support gtk 3.8 or later, then you can derive your 
classes from the relevant Gtk*Accessible classes and call 
gtk_widget_class_set_accessible_type in the custom widget's class init 
function. If you also need to support earlier versions of gtk, then it is 
a bit of a mess, and your best bet is probably to override get_accessible 
in the class init function and create a base class adapted from, say, 
GtkWidgetAccessible. For an example of how to do this, you could look at 
my patch on https://bugzilla.gnome.org/show_bug.cgi?id=669441 (the patch 
in comment 7, not the much cleaner patch in comment 4, but the latter is a 
good example if you only need to support gtk+ 3.8 and later). One option 
might be to encapsulate the accessibility code with #if 
GTK_CHECK_VERSION(3.8.0), depending on whether it's important to make it 
work for gtk 2 as well.

Feel free to write if you have other questions. Sorry for not being able 
to suggest anything more straight-forward in terms of documentation, but, 
anyway, it would be good for more people to understand how all of this 
works.

Thanks,
-Mike

On Tue, 15 Jul 2014, Mike Ray wrote:

> He also said that if I add atk accessibility to it he will incorporate
> the changes.
>
> But as I don't currently know how to do this, it is likely to take me a
> while.
>
> If anybody can point me at atk tutorials and tips I'd like to have a go
> as I am a big fan of SciTE on Windows.
>
> Mike