Re: [boost] RE: Re: GUI library - another one

From: Vladimir Prus (ghost_at_[hidden])
Date: 2004-03-04 09:49:41

Peter Dimov wrote:

> >    window make_graph_widget()
> >    {
> >          windows w;
> >          w.on_draw = &draw_the_graph;
> >          w.on_mouse_click = &handle_click;
> >          w.on_mouse_right_click = &handle_right_click;
> >          return w;
> >    }

> > and isn't this too complex a solution?
>
> No. The alternative solution is comparable in complexity, 

Well, except for impicit *this pointer, which makes member function a bit 
easier to write.

> and as soon as
> you add another graph widget that has different left or right click
> behaviors, or make w change its appearance dynamically on response to a
> combo box cb (by just assigning different drawing functions to w.on_draw in
> cb.on_change), you'll see why the event-based model is superior. 

Good point. Okay, if I ever get to implement my graph drawer and the proposed 
library will be mature enough, I'll see how this approach works out.

> It's not a
> new invention, just look at Delphi.

Last time I tried, a click on event created a method linked to that event. 
Ah... nothing prevents me to implement 'on_draw' as member functions bound to 
the signal. Yes, that's definititely similiar.

- Volodya