Making h:panelGroup clickable, and send back repeated variable - ajax

Question

I need to make a panelGrid (one of man that are populated from a list of objects) clickable, and then send the item associated with it to the backing bean.
My HTML so for:
<ui:repeat var="searchItem" value="#{bean.filteredSearchItems}" varStatus="searchResult">
<h:panelGrid>
<!-- I get some info here from the searchResult object -->
</h:panelGrid>
<f:ajax event="click" listener="{bean.clickFlight}" />
<f:param name="lfi" value="#{searchResult.index}" />
</ui:repeat>
I know that (in my backing bean) I need a function called clickSearchItem() that can handle the ajax call, so to test all of this, I did the following in my backing bean:
public void clickFlight()
{
HttpServletRequest req = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
String lfi = req.getParameter("lfi");
if (lfi == null)
log.info("LFI WAS RETURNED AS NULL :(");
log.info("HOPEFULLY AN INDEX OF SOME SORT!: " + lfi);
}
Nothing is getting logged - the click doesn't register. Has anyone else had this problem? Does anyone know how to solve it?

Answer 1

The <f:ajax> needs to be nested into a component implementing ClientBehaviorHolder. If you intend to use <h:panelGrid> (which generates a HTML <table>) for that, then you should be nesting the <f:ajax> in the component itself.
<h:panelGrid>
<f:ajax event="click" listener="{bean.clickFlight}" />
<!-- I get some info here from the searchResult object -->
</h:panelGrid>
The <f:param> is only recognized by renderer of <h:outputFormat> and <h:commandXxx>. Provided that you're targeting a Servlet 3.0 compatible container (Tomcat 7, Glassfish 3, JBoss 6/7, etc) which thus supports EL 2.2, then you can just pass it as method argument instead:
<h:panelGrid>
<f:ajax event="click" listener="{bean.clickFlight(searchResult.index)}" />
<!-- I get some info here from the searchResult object -->
</h:panelGrid>
you can even pass the whole object if preferred:
<h:panelGrid>
<f:ajax event="click" listener="{bean.clickFlight(searchResult)}" />
<!-- I get some info here from the searchResult object -->
</h:panelGrid>
An alternative, if you need <f:param> per se, would be to use <h:commandLink> instead.
<h:commandLink>
<f:ajax event="click" listener="{bean.clickFlight(searchResult)}" />
<f:param name="lfi" value="#{searchResult.index}" />
<h:panelGroup>
<!-- I get some info here from the searchResult object -->
</h:panelGroup>
</h:commandLink>