(module client mzscheme
  
  (require (lib "mred.ss" "mred")
           (lib "class.ss"))
  
  (define frame
    (new frame% 
         (label "Frame label")
         (width 400)
         (height 400)))
  
  (define msg
    (instantiate message%
      ("No events so far..." frame)))
  
  (instantiate button% ()
    (label "Click Me")
    (parent frame)
    ;; Callback procedure for a button click
    (callback (lambda (button event)
                (send msg set-label "Button click"))))
  
  (send frame show #t)

);module