Re: Keyboard Navigation Code - XPathEvaluate - need help

Ady Shimony wrote:


> My XUL looks like this
> 
> <?xml version="1.0" encoding="UTF-8"?>
> <?xml-stylesheet href="/css/default_PC.css" type="text/css"?>
> <window width="602" height="452" style="background: #FFFFFF;" 
> xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" 
> title="Screen2" UserEdit="yes" align="left">
> <stack>
> <button id="Button1" width="80" height="28" left="44" top="41" 
> style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
> Button"></button>
> <button id="Button2" width="80" height="28" left="155" top="40" 
> style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
> Button"></button>
> <button id="Button3" width="80" height="28" left="249" top="37" 
> style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
> Button"></button>
> </stack>
> </window>
> 
> I don't understand how to make the resolver undertand ?

Here is a working example, the prefix 'xul' is bound to the XUL 
namespace so that in XPath expression you can use 'xul:xulelementname' 
e.g. 'xul:button' to access XUL elements:

<?xml version="1.0" encoding="UTF-8"?>
<window width="602" height="452" style="background: #FFFFFF;"
xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
xmlns:xhtml="http://www.w3.org/1999/xhtml"
title="Screen2" align="left">
<script type="text/javascript">
<![CDATA[
function testXPathEvaluation () {
   var resolver = document.createNSResolver(document.documentElement);
   var xpathResult = document.evaluate(
     '//xul:button | //xhtml:input',
     document,
     function lookupNamespaceURI (prefix) {
       var nsURI = null;
       switch (prefix) {
         case 'xul':
           nsURI = 
'http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul';
           break;
         default:
           nsURI = resolver.lookupNamespaceURI(prefix);
           break;
       }
       return nsURI;
     },
     XPathResult.ORDERED_NODE_ITERATOR_TYPE,
     null
   );
   var result = '';
   var node;
   while ((node = xpathResult.iterateNext())) {
     result += 'nodeType: ' + node.nodeType + '; nodeName: ' + 
node.nodeName + '\r\n';
   }
   alert(result);
}
]]>
</script>
<stack>
<button id="Button1" width="80" height="28" left="44" top="41"
style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
Button"></button>
<button id="Button2" width="80" height="28" left="155" top="40"
style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
Button"></button>
<button id="Button3" width="80" height="28" left="249" top="37"
style="background: #5F6BA7;border-color: #6E7AB0;" label="My 
Button"></button>
<xhtml:input type="button" value="html click button" 
onclick="testXPathEvaluation();"/>
</stack>
</window>

As said the problem with XPath (XPath 1.0) is that any XPath expression 
trying to access elements in the default namespace (e.g. <element 
xmlns="http://example.com/whatever">) needs to use a prefix bound to 
that namespace.

-- 

	Martin Honnen
	http://JavaScript.FAQTs.com/