Source code in the common programming language

(use-package :ltk)

(defun show-message (text)
  "Show message in a label on a Tk window"
  (with-ltk ()
      (let* ((label (make-instance 'label :text text))
             (button (make-instance 'button :text "Done"
                                    :command (lambda () 
                                               (ltk::break-mainloop)
                                               (ltk::update)))))
              (pack label :side :top :expand t :fill :both)
              (pack button :side :right)
              (mainloop))))

(show-message "Goodbye World")


(in-package :clim-user)

(defclass hello-world-pane
    (clim-stream-pane) ())

(define-application-frame hello-world ()
  ((greeting :initform "Goodbye World"
             :accessor greeting))
  (:pane (make-pane 'hello-world-pane)))

;;; Behaviour defined by the Handle Repaint Protocol
(defmethod handle-repaint ((pane hello-world-pane) region)
  (let ((w (bounding-rectangle-width pane))
        (h (bounding-rectangle-height pane)))
    ;; Blank the pane out
    (draw-rectangle* pane 0 0 w h
                     :filled t
                     :ink (pane-background pane))
    ;; Draw greeting in center of pane
    (draw-text* pane
                (greeting *application-frame*)
                (floor w 2) (floor h 2)
                :align-x :center
                :align-y :center)))

(run-frame-top-level
 (make-application-frame 'hello-world
   :width 200 :height 200))