1 Overview

The GTK+ wrapper for Guile is a part of Guile-GNOME. It's a good idea to read the (gnome gobject) documentation first. See Contents.

1.1 Example usage

The following code can be found in the file gtk/examples/hello.scm in your distribution.

 (use-modules (oop goops) (gnome gobject) (gnome gtk))
 
 ;; define the app as a function -- there are many other ways to do
 ;; this, of course...
 
 (define (hello)
 ;; every widget has a class. here we define a window and a button.
 (let* ((window (make <gtk-window> #:type 'toplevel))
 	 (button (make <gtk-button> #:label "Hello, World!")))
 
 (gtk-container-set-border-width window 10)
 (gtk-container-add window button)
 
 ;; of course you can attach a lambda to a signal :-)
 (gtype-instance-signal-connect button 'clicked
 (lambda (b) (gtk-main-quit)))
 
 (gtk-widget-show-all window)
 
 ;; this will block until gtk-main-quit is called...
 (gtk-main)))
 
 ;; meaning this blocks until the button is clicked.
 (hello)

1.2 hello world, improved

There's something about this that resembles programming in C a little bit too much. In Python, you can just do window.add(button). That's a lot less typing. In GOOPS, the object framework for Guile, methods are implemented a bit differently – See (gnome gobject generics). If we use the GOOPS methods, hello-generics.scm looks a bit different:

 (use-modules (oop goops) (gnome gobject) (gnome gtk)
 (gnome gobject utils))
 
 (define (hello)
 (let* ((window (make <gtk-window> #:type 'toplevel))
 	 (button (make <gtk-button> #:label "Hello, World!")))
 
 ;; since window is a container, this generic maps onto the
 ;; function gtk-container-set-border-width
 
 (set-border-width window 10)
 
 ;; note that we can set the border width with a gobject property
 ;; as well:
 
 (gobject-set-property window 'border-width 15)
 
 ;; (gnome gobject generics), re-exported by (gnome gtk), defines a
 ;; generic `set' method for gobject-set-property, se we can also
 ;; do it like this:
 (set window 'border-width 20)
 
 ;; or, like this, using with-accessors from (gnome gobject utils):
 (with-accessors (border-width)
 (set! (border-width window) 20))
 
 ;; this is much less typing :-)
 (add window button)
 
 ;; see (gnome gobject generics) for a full list of gobject generic
 ;; functions
 (connect button 'clicked (lambda (b) (gtk-main-quit)))
 
 ;; generic functions for .defs apis are defined in the .defs files,
 ;; not manually
 (show-all window)
 
 (gtk-main)))
 
 (hello)