A brief example

(defun my-callback (widget call-data quit)
  (format t "Got callback on ~A~%" widget)
  (format t "Callback reason was ~A~%" (any-callback-reason call-data))
  (format t "Quit button is ~A~%" quit))

(defun test-init ()
  (let* ((shell (create-application-shell))
	 (rc (create-row-column shell "rowColumn"))
	 (quit (create-push-button-gadget rc "quitButton"
					  :label-string "Quit"))
	 (button (create-push-button-gadget rc "button"
					    :highlight-on-enter t
					    :shadow-thickness 0
					    :label-string "This is a button")))

    (add-callback quit :activate-callback #'quit-application-callback)
    (add-callback button :activate-callback 'my-callback quit)

    (manage-child rc)
    (manage-children quit button)
    (realize-widget shell)))

(defun test ()
  (run-motif-application 'test-init))