What's missing with this code?

[benjes]

Hi,

I have a rich:dataTable which I want to scroll via a javascript function (a4j:jsFunction).

<a4j:jsFunction name="nextPage" reRender="tableID" action="#{backBean.scrollPage()}">
 <a4j:actionparam name="FieldID" />
 <a4j:actionparam name="pageDirection" />
</a4j:jsFunction>

<a4j:commandButton value=">" onclick="nextPage('tableID','next')"/>

On the server side I have the following code:

public void scrollPage(){

 log.info("FacesContext "+facesContext);
 Map<String, String>parameters = facesContext.getExternalContext().getRequestParameterMap();
 Iterator<String> iter = parameters.keySet().iterator();
 Iterator<String> iter2 = parameters.values().iterator();
 while(iter.hasNext()){
 log.info(iter.next()+"="+iter2.next());
 }
 UIViewRoot root = facesContext.getViewRoot();
 if(parameters.containsKey("FieldID")){
 log.info("ID is "+parameters.get("FieldID"));
 String request = parameters.get("pageDirection");
 log.info("Direction "+request);
 UIComponent comp = root.findComponent(parameters.get("FieldID"));
 if(comp instanceof UIData){
 UIData data= (UIData)comp;
 log.info(comp.toString());
 int first = data.getFirst();
 int itemcount = data.getRowCount();
 int pagesize = data.getRows();
 log.info("first "+first+" itemcount "+itemcount);
 if(pagesize <=0)
 pagesize = itemcount;
 if(request.equals("next")){
 first += pagesize;
 }else if(request.equals("prev")){
 first -= pagesize;
 }
 if(first+pagesize > itemcount)
 first = itemcount-pagesize;
 if(first <0)
 first = 0;
 log.info("Setting new first "+first);
 data.setFirst(first);
 log.info("New first "+data.getFirst());
 }else{
 log.warn("Component not found");
 }
 }

 }

That all works fine. It finds the org.richfaces.component.html.HtmlDataTable sets first to first+pagesize
but still the actual table on the client doesn't get updated. Have I missed something here.
I have checked the Ajax response and it still contains the table elements
from the first page.

Thanks

Immo