Re: [boost] GUI library - another one

From: Peter Dimov (pdimov_at_[hidden])
Date: 2004-03-03 11:24:45

David Turner wrote:
> Hello
>
> It seems that the idea of adding a medium-complexity GUI library to boost
> is popular, but that there are widely varying opinions on how it should be
done.
>
> I've written a first draft of a library that fulfils most of my
> expectations.  It's available at http://www.turn.co.za/david/gui.  It
> supports two platforms (Win32 and GTK2), and four user interface elements
> or widgets (window, label, button, text-entry).  The design is such that
> it is extremely easy to support new platforms or widgets.

Looks very promising!

Why is cast<> using a what looks like a homebrew RTTI system? Is there
something that makes dynamic_pointer_cast<T::element_type>(w) inappropriate?

Still on the cast<> subject, it should probably signal failure by throwing
an exception derived from std::bad_cast, or maybe just return NULL, to allow
the usual

if( grid g = cast<grid>(w) )
{
// ...
}

Have you considered the 'on_delete', 'on_change' naming scheme for signals
(events)? It seems more GUI/RAD-like.

Finally, when I see

    test->contain(create_label(test,
        "You pressed the \"Click me!\" button!\nHow clever!"));

I wonder whether it would be feasible to eliminate the inner 'test', as it's
logically redundant (a window probably can't contain something that is
parented by another window). Although this would probably turn the
architecture on its head, as it would require a new concept, a 'free
widget'.