[Help-smalltalk] Subclassing GTK "Classes" possible?

[Joachim Jaeckel]

Hello,

I'm currently trying something like
"GTK.GtkWindow subclass: MainWindow"

But maybe, that is not possible, because GtkWindow is no real class, but 
a binding?

The reason, why I come to the question is, if I try the following code 
in the open-method:

GTK.GtkWindow subclass: MainWindow [
      MainWindow class >> open [
              | r |
              <category: 'user interface'>

              r := self new: GTK.Gtk gtkWindowToplevel.
              r initialize.
              r show.
              ^r
      ]

       initialize [
                ...
       ]
]

The VM errors out that "initialize" is not understood from GtkWindow.

I know I have a lot to learn, currently I'm a bit confused about the 
fact, that "new" is a class-method and with the things that have an 
association with that.

In Java I would call in the constructor of a subclassed class e.g. 
super(bla); to initialize the object. How could that be done in smalltalk?

E.g. in my class, a class-method new could for instance call the super 
new ... but would that not result in a new object?

MainWindow class >> new: aType [
        super new: aType
]

Thanks in advance,
Joachim.