[ltk-user] Q about canvas item handles

[Daniel Herring]

Why isn't HANDLE (for canvas items) exported from :ltk?

"Hand to forehead" when I figured out why the following didn't work.

(defpackage :p
   (:use :cl :ltk))
(in-package :p)
(defun test ()
   (let* (...
          (c (... 'canvas ...))
          (o (make-instance 'canvas-oval :canvas c :x0 ...)))
     (itemconfigure c (slot-value o 'handle) ...)))


Alternatively, would it make sense to have
(defmethod itemconfigure ((canvas canvas) (canvas-item item) ...))
do the right thing?  Possible patch attached.

Thanks,
Daniel
-------------- next part --------------
From 4d678a213b251e9f3905590fc525bb3bde118e37 Mon Sep 17 00:00:00 2001
From: D Herring <dherring at at.tentpost.dot.com>
Date: Tue, 14 Jul 2009 01:20:22 -0400
Subject: [PATCH] rework itemconfigure

- use another defmethod to replace stringp
- add methods to handle canvas-items
---
 ltk.lisp |   25 ++++++++++++++++++++-----
 1 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/ltk.lisp b/ltk.lisp
index 3d0011d..cd02f72 100644
--- a/ltk.lisp
+++ b/ltk.lisp
@@ -3219,19 +3219,34 @@ set y [winfo y ~a]
 
 (defgeneric itemconfigure (widget item option value))
 
-(defmethod itemconfigure ((widget canvas) item option value)
-  (format-wish "~A itemconfigure ~A -~(~A~) {~A}" (widget-path widget) item option
-	    (if (stringp value) ;; There may be values that need to be passed as
-		value           ;; unmodified strings, so do not downcase strings
-	      (format nil "~(~a~)" value))) ;; if its not a string, print it downcased
+(defmethod itemconfigure ((widget canvas) item option (value string))
+  "Some values need to be passed as unmodified strings, so do not downcase."
+  (format-wish "~A itemconfigure ~A -~(~A~) {~A}" (widget-path widget) item option value)
   widget)
 
+(defmethod itemconfigure ((widget canvas) item option value)
+  (format-wish "~A itemconfigure ~A -~(~A~) {~(~a~)}" (widget-path widget) item option value)
+  widget)
 
 ;;; for tkobjects, the name of the widget is taken
 (defmethod itemconfigure ((widget canvas) item option (value tkobject))
   (format-wish "~A itemconfigure ~A -~(~A~) {~A}" (widget-path widget) item option (widget-path value))
   widget)
 
+(defmethod itemconfigure ((widget canvas) (item canvas-item) option (value string))
+  "Some values need to be passed as unmodified strings, so do not downcase."
+  (format-wish "~A itemconfigure ~A -~(~A~) {~A}" (widget-path widget) (handle item) option value)
+  widget)
+
+(defmethod itemconfigure ((widget canvas) (item canvas-item) option value)
+  (format-wish "~A itemconfigure ~A -~(~A~) {~(~a~)}" (widget-path widget) (handle item) option value)
+  widget)
+
+;;; for tkobjects, the name of the widget is taken
+(defmethod itemconfigure ((widget canvas) (item canvas-item) option (value tkobject))
+  (format-wish "~A itemconfigure ~A -~(~A~) {~A}" (widget-path widget) (handle item) option (widget-path value))
+  widget)
+
 (defgeneric itemlower (w i &optional below))
 (defmethod itemlower ((widget canvas) item &optional below)
   (format-wish "~A lower ~A ~@[~A~]" (widget-path widget)
-- 
1.6.0.2