#lang racket/gui

(define my-tabs-list '("Tab 0" "Tab 1" "Tab 2"))

(define root-wnd
  (new frame%
       [label "Test"]
       [width 300]
       [height 300]
       ))

(define tab-panel
  (new tab-panel%
       [parent root-wnd]
       [choices my-tabs-list]
       [callback (lambda (tp e) (change-tab (send tp get-selection)))]))

(define (change-tab tab-no)
  (case tab-no
    [(0) (send tab-panel change-children (lambda (children) (list a-panel)))]
    [(1) (send tab-panel change-children (lambda (children) (list b-panel)))]
    [(2) (send tab-panel change-children (lambda (children) (list c-panel)))]
    ))

(define a-panel
  (new panel%
       [parent tab-panel]
       ))

(define a-panel-message
  (new message%
       [parent a-panel]
       [label "A-panel"]
       ))

(define b-panel
  (new panel%
       [parent tab-panel]
       ))

(define b-panel-message
  (new message%
       [parent b-panel]
       [label "B-panel"]
       ))

(define c-panel
  (new panel%
       [parent tab-panel]
       ))

(define c-panel-message
  (new message%
       [parent c-panel]
       [label "C-panel"]
       ))

(change-tab 0)

(send root-wnd show #t)