Why usage of any a4j element in jsf add to page code second body and head tags?

问题

In my jsf page code I have a structure similiar to this one :

<frameset id="navframeset">
   <frame name="navframe" src='<c:url value="TopNavigation.jsf"/>'/>
   <frameset>
      <frame name="leftframe" src='<c:url value="Test1.jsf"/>'/>
      <frame name="tabbedframe" src='<c:url value="Test2.jsf"/>' />
</frameset>

In Test2.jsf i included following richfaces libraries :

<%@ taglib uri="http://richfaces.org/a4j" prefix="a4j"%>
<%@ taglib uri="http://richfaces.org/rich" prefix="rich"%>

When I try to use any of a4j element in a page code, for instance a4j:button, then this code is generated in my output html file :

<head>...</head>
<body>..</body>
<head><script xmlns="http://www.w3.org/1999/xhtml">A4J.AJAX._scriptEvaluated=true;</script></head>
<body marginwidth="0" marginheight="0"></body>

These two last lines are added when I use a4j element in my page code and it duplicate existing body and html tags(first two lines). Version of richfaces which I'm using is 3.1.6.SR1. Can anybody give me a hint how to fix it ?

回答1:

Ok, this is an issue of 3.1.6.SR1 library, the last one which support jsf 1.1 version. I have found in google following solution https://developer.jboss.org/thread/196997?tstart=0. However it's not perfect and doesn't work in every situation. Because of this i was trying to solve this issue in other ways and as suggestion in above link I've changed AJAX.js file form richfaces-impl.jar. I took AJAX.js file from richfaces-3.2 version and replace code in 3.1.6.SR1. Following parts should be changed :

line 1412 // Added A4J.AJAX.TestScriptEvaluation();

A4J.AJAX.processResponse = function(req) {
        A4J.AJAX.TestScriptEvaluation();
        var options = req.options;
        var ajaxResponse = req.getResponseHeader('Ajax-Response');

line 2014 TestScriptEvaluation function should be replaced to the following one:

//Test for re-evaluate Scripts in updated part. Opera & Safari do it.
A4J.AJAX._scriptEvaluated=false;
A4J.AJAX.TestScriptEvaluation = function () {
if ((!document.all || window.opera) && !A4J.AJAX._scriptTested){


    try{    
        // Simulate same calls as on XmlHttp
        var oDomDoc = Sarissa.getDomDocument();
        var _span = document.createElement("span");
        document.body.appendChild(_span);
        // If script evaluated with used replace method, variable will be set to true
        var xmlString = "<html xmlns='http://www.w3.org/1999/xhtml'><sc"+"ript>A4J.AJAX._scriptEvaluated=true;</scr"+"ipt></html>";
        oDomDoc = (new DOMParser()).parseFromString(xmlString, "text/xml");
        var _script=oDomDoc.getElementsByTagName("script")[0];
        if (!window.opera && !A4J.AJAX.isWebkitBreakingAmps() && _span.outerHTML) {





            _span.outerHTML = new XMLSerializer().serializeToString(_script); 
        } else {
            var importednode ;
            importednode = window.document.importNode(_script, true);
            document.body.replaceChild(importednode,_span);
        }

    } catch(e){ /* Mozilla in XHTML mode not have innerHTML */ };

}

      A4J.AJAX._scriptTested = true;
    }

And that's all. With this changes this issue is not exists anymore.

来源：https://stackoverflow.com/questions/34656354/why-usage-of-any-a4j-element-in-jsf-add-to-page-code-second-body-and-head-tags

标签

jsf

iframe

richfaces

ajax4jsf

jsf-1.1