diff -r 5e9d7f92d5d2 -r 5e13b1ac2886 javaquery/api/src/main/java/org/apidesign/bck2brwsr/htmlpage/api/Canvas.java
--- a/javaquery/api/src/main/java/org/apidesign/bck2brwsr/htmlpage/api/Canvas.java	Tue Jan 22 17:28:01 2013 +0100
+++ b/javaquery/api/src/main/java/org/apidesign/bck2brwsr/htmlpage/api/Canvas.java	Sat Jan 26 08:47:05 2013 +0100
@@ -47,7 +47,7 @@
 
     @JavaScriptBody(
             args = {"el"},
-            body = "var e = window.document.getElementById(el.fld_id);\n"
+            body = "var e = window.document.getElementById(el._id());\n"
             + "return e.getContext('2d');\n")
     private native static Object getContextImpl(Canvas el);