Easy GUI Currency Converter

The preliminary specification of Easy GUI is on the Easy GUI page.

This example implements the end-user functionality of Apple's Currency Converter example, but it uses Easy GUI rather than Cocoa. It does not duplicate the Model-View-Controller implementation used by the Cocoa example.

(in-package :easygui-user)

(defclass converter-window (window)
   ()
   (:default-initargs :size (point 383 175)
     :position (point 125 513)
     :title "Currency Converter"
     :resizable-p nil
     :minimizable-p t))

(defmethod initialize-view :after ((cw converter-window))
  (let* ((currency-form (make-instance 'form-view
                          :autosize-cells-p t
                          :interline-spacing 9.0
                          :position (point 15 70)                          
                          :size (point 353 90)))
	 (convert-button (make-instance 'push-button-view
                           :default-button-p t
                           :text "Convert"
                           :position (point 247 15)))
	 (line (make-instance 'box-view
                 :position (point 15 59)
                 :size (point 353 2)))
	 (entries (add-entries currency-form
			       "Exchange Rate per $1:"
			       "Dollars to Convert:"
			       "Amount in other Currency:")))
    (setf (action convert-button)
          #'(lambda ()
              (let ((n1 (read-from-string (entry-text currency-form 1)
                                          nil nil))
                    (n2 (read-from-string (entry-text currency-form 0)
                                          nil nil)))
                (when (and (numberp n1) (numberp n2))
                  (setf (entry-text currency-form 2)
                        (prin1-to-string (* n1 n2)))))))
    (setf (editable-p (car (last entries)))
          nil)
    (add-subviews cw currency-form line convert-button)
    (window-show cw)))

;(make-instance 'converter-window)