Email55555 wrote:

> In fact, I ask SWT, that is because, I want learn a GUI framework
> that can re-use, ( for example, in java and in ruby, also multi-platform ).

I'm not sure I understand your requirements. If you're wanting a GUI 
framework that is both multi-platform *and* usable in Java and Ruby, 
you're narrowing the field pretty quickly. Have you considered using 
JRuby (http://jruby.sourceforge.net)? I unfortunately haven't had a 
chance to look at this yet, but it's my understanding that one can use 
the Swing classes inside a JRuby application.

> Mmmm... let me explain my question, let's say if you do not have much time,
> and you want to pick up a GUI framework to learn, which one you suggest?
> FOX ? TK? Gtk? Qt? ...

I'm obviously biased towards FOX, but I don't really know how to answer 
that question. If you've ever used one of them in some other language 
(e.g. you've written a C program that used GTK+, or a Python program 
that used PyQt) you should pick the one that you're already familiar 
with; it's likely that most of your knowledge about how to use that 
toolkit will transfer over to its Ruby binding. But if you don't know 
*anything* about any of the toolkits, you'll probably want to start with 
Ruby/Tk. There are a lot of people still using Ruby/Tk (or who have at 
least used it in the past) and there's some documentation for Ruby/Tk 
here and there.

Note that my response is based on your restriction that you don't have 
much time. If you have more time, I would invest the effort in learning 
how to use one of the others (i.e. FOX, GTK+ or Qt).