Entry

LISP: Allegro Franz Lisp: Microsoft: Windows: Button: Simple: How to write program, which assigns 3?

Jan 25th, 2004 14:53
Knud van Eeden,

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--- Knud van Eeden --- 25 January 2004 - 09:32 pm --------------------

LISP: Allegro Franz Lisp: Microsoft: Windows: Button: Simple: How to 
write program, which assigns 3?

---

Steps: Overview:

 1. -Create a new application

     1. Run Allegro Lisp

 2. -Put a button on the form

     1. Click once on the leftmost button on the palette

     2. Click once on the form

     3. That will place a button on the form

 3. -Put some code in the event for this button

     1. Double click on the button

     2. -click button 'Events'
         in the 'Inspect' window

     3. -Double click on the 'On click' event line

     4. -That will add some default code

--- cut here ---------------------------------------------------------


;; Code for the dialog :form1

(in-package :common-graphics-user)


(defun form1-button4-on-click (dialog widget)
  (declare (ignore-if-unused dialog widget))

  t)

--- cut here ---------------------------------------------------------

 4. -To show the value (so you set 'x=3', then show 'x' on the title
     of the button, just add the following lines:

  ; this is equivalent to 'x=3'

  ; tried also to use ( = x 3 )

     (setq x 3)

  ; first search for the button4 in the existing controls,
  ; and assign this to a variable

     (setq mybutton (find-component :button4 (parent widget)))

  ; then set its property 'title'

     (setf (title mybutton) x)

 5. -So all together that gives the following code:

--- cut here ---------------------------------------------------------

(defun form1-button4-on-click (dialog widget)

  (declare (ignore-if-unused dialog widget))

  (setq x 3)

  ; first search for the button4 in the existing controls,
  ; and assign this to a variable

    (setq mybutton (find-component :button4 (parent widget)))

 ; then set its property 'title'

    (setf (title mybutton) x)

--- cut here ---------------------------------------------------------

 6. -Run this code

     1. Click on the '>' in the menu

     2. Ignore the possible warning, by clicking he

     3. Then click on the button

        1. It will change its title to '3'

            +-----------------------+
            |                       |
            |           3           |
            |                       |
            +-----------------------+

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