You could register it as JSF ajax callback handler by jsf.ajax.addOnEvent:
<script>
jsf.ajax.addOnEvent(foo);
</script>
with
<script>
function foo(data) {
var ajaxStatus = data.status; // Can be "begin", "complete" and "success".
switch (ajaxStatus) {
case "begin": // Right before sending ajax request.
// ...
break;
case "complete": // Right after receiving ajax response.
// ...
break;
case "success": // When ajax response is successfully processed.
// ...
break;
}
}
</script>
where the data object has several useful XHR derived properties which is described in table 14-4 of JSF 2.0 specification (click the For Evaluation link). Here’s an extract of relevance:
TABLE 14-4 Event Data Payload
Name Description/Value ------------- ---------------------------------------------------- type “event” status One of the events specified in TABLE 14-3 source The DOM element that triggered the Ajax request. responseCode Ajax request object ‘status’ (XMLHttpRequest.status); Not present for “begin” event; responseXML The XML response (XMLHttpRequest.responseXML); Not present for “begin” event; responseText The text response (XMLHttpResponse.responseTxt); Not present for “begin” event;
As an alternative, a XHTML-declarative way would be to just embed the script call in a JSF component with an id and let the ajax call re-render it. The component should in turn render the script conditionally based on FacesContext#isPostback().
<h:form>
<h:commandButton value="Submit" action="#{bean.submit}">
<f:ajax render=":myscript">
</h:commandButton>
</h:form>
<h:panelGroup id="myscript">
<h:outputScript rendered="#{facesContext.postback}">foo();</h:outputScript>
</h:panelGroup>
Most component libraries have however better abstracted support for this. Since you didn’t mention which one you’re using so that a more suited answer can be given, here’s just a random example based on PrimeFaces command button.
<p:commandButton value="Submit" action="#{bean.submit}" oncomplete="foo();" />
Refer the documentation of the component library you’re using.