Is it possible to trigger action in backing bean on page unload event?

Question

Hi,
There is a RichPopup in my page which has a Listener to save data or not by user choice "Data change detected, do you want to save those changes?"
I've tried with the javascript event 'window.onbeforeunload', but this way must be fit with a Servlet function which I am not allowed to use.
The attibute 'onunload' in the tag '<af:document>' seems useless. Even there is few description or example in the 'Tag Reference'.
So, is it possible to trigger action in backing bean on page unload event? Thanks in advance for helping.
Viva

Answer 1

Hi Frank
Thanks for helping, I've tried in your way. My codes are like below:
Page codes:
<?xml version='1.0' encoding='UTF-8'?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1"
          xmlns:f="http://java.sun.com/jsf/core"
          xmlns:h="http://java.sun.com/jsf/html"
          xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
  <jsp:directive.page contentType="text/html;charset=UTF-8"/>
  <f:view>
    <af:document id="d1" clientComponent="true" title="viva test">
      <af:resource type="javascript">
        if (!window.addEventListener) {
            // alert('window.addEventListener is not supported in IE8. Override it!');
            window.addEventListener = function (type, listener, useCapture) {
                window.attachEvent('on' + type, function() {listener(event)});
        window.addEventListener('beforeunload', function (){performUnloadEvent()}, false);
        function performUnloadEvent() {
          var eventSource = AdfPage.PAGE.findComponentByAbsoluteId('d1');
          //var x and y are dummy variables obviously neeed to keep the page
          //alive for as long it takes to send the custom event to the server
          var x = AdfCustomEvent.queue(eventSource, 'handleOnUnload', {args:'noargs'}, false);
          var y = 0;
      </af:resource>
      <af:serverListener type="handleOnUnload" method="#{vivaTestBean.testOnUnload}"/>
      <!--
      <af:form id="f1">
        <af:commandButton text="Unload" id="cb1" action="unload"/>
      </af:form>
      -->
    </af:document>
  </f:view>
</jsp:root>The backing bean codes:
public class VivaTestBean {
    public VivaTestBean() {
    public void testOnUnload(ClientEvent clientEvent) {
        System.out.println("Thanks God");
}The first way which triggers a 'unload' event by clicking a button DO WORKS. :)
But when I changed the triggered way by changing the <af:document> to clientComponent as what you did, the 'onbeforeunload' event won't come out when I refreshed or closed the page.
That doesn't make sence, since I think the two ways to trigger a 'unload' event are the same.
Edited by: 841766 on 2011-3-7 上午1:13