Trouble updating view from AJAX

[Allen Legge]

I have been searching for several days for a solution that works, but I haven't found anything that resolves my problem thus far. So here it is:

I have two images. I want to be able to click them and kick off a call to a listener in Java to change a value in the bean. I also want the view to update my dropdown (labeled "menuModel") to either be rendered or not, depending on which image I click. Alternatively, I would be fine with the dropdown simply being disabled and enabled for the same criteria.

So far, the listener kicks off fine, and the value gets updated correctly in the bean. However, the view never gets updated. I have tried this a hundred different ways, but nothing seems to work. If I hit refresh on my browser, the view updates. But I want it to do it automatically.

What am I doing wrong?

NOTE: I am using standard JSF 2.1.


<div style="font-family: Verdana; font-size: 10pt; color: #FFFFFF"> <h2>Calibrations</h2> <h:form id="tunerSelectionForm" style="color: #000000"> <h:commandLink> <f:param name="tunerSelection" value="R" /> <h:graphicImage id="imgR" value="/images/r.png" /> <f:ajax event="click" render="grpMenuModel" listener="#{calibrationsBacking.tunerSelectionListener}" /> </h:commandLink> <h:commandLink> <f:param name="tunerSelection" value="S" /> <h:graphicImage id="imgS" value="/images/s.png" /> <f:ajax event="click" render="grpMenuModel" listener="#{calibrationsBacking.tunerSelectionListener}" /> </h:commandLink> <br /> <br /> <h:panelGroup id="grpMenuModel"> <h:selectOneMenu id="menuModel" onchange="submit()" rendered="#{calibrationsBacking.tuner == 'S'}" value="#{calibrationsBacking.model}" valueChangeListener="#{calibrationsBacking.modelChangeListener}"> <f:selectItem itemValue=" " itemLabel="-- Type --" /> <f:selectItem itemValue="B" itemLabel="Model B" /> <f:selectItem itemValue="T" itemLabel="Model T" /> </h:selectOneMenu> </h:panelGroup> </h:form> </div>

@ManagedBean(name="calibrationsBacking")
@SessionScoped
public class CalibrationsBacking {
	private char tuner = '\0';
	private char model = '\0';
	
	public boolean tunerSelectionListener() {
		ExternalContext externalContext =
				FacesContext.getCurrentInstance().getExternalContext();
		String tunerSelection =
				externalContext.getRequestParameterMap().get("tunerSelection");
		setTuner(tunerSelection);
		
		return true;
	}
	
	public void modelChangeListener(ValueChangeEvent event) {
		Character modelValue = (Character)event.getNewValue();
		
		if(modelValue == null)
			return;
		
		model = modelValue;
	}

	public String getTuner() {
		if(tuner == '\0')
			return null;
		
		return String.valueOf(tuner);
	}

	public void setTuner(String tuner) {
		if(tuner == null || tuner.length() == 0)
			this.tuner = '\0';
		else
			this.tuner = tuner.charAt(0);
	}

	public String getModel() {
		return String.valueOf(model);
	}

	public void setModel(String model) {
		if(model == null || model.length() == 0)
			this.model = '\0';
		else
			this.model = model.charAt(0);
	}
}

[chets patel]

Can you try adding "menuModel" in render attribute of ajax event like below.

<f:ajax event="click" render="grpMenuModel menuModel"  
                    listener="#{calibrationsBacking.tunerSelectionListener}" />  

[Allen Legge]

It didn't have an effect on it unfortunately.

I did notice something in the Tomcat window though. I have no idea what this means, but it gets thrown every time I click one of the images:

Sep 27, 2014 5:01:02 PM com.sun.faces.application.view.FaceletViewHandlingStrategy handleRenderException
SEVERE: Error Rendering View[/calibrations.xhtml]
java.lang.NullPointerException
        at org.apache.myfaces.trinidadinternal.renderkit.core.ppr.PPRResponseWriter.<init>(PPRResponseWriter.java:62)
        at org.apache.myfaces.trinidadinternal.context.PartialViewContextImpl._processRender(PartialViewContextImpl.java:307)
        at org.apache.myfaces.trinidadinternal.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:189)
        at javax.faces.component.UIViewRoot.encodeChildren(UIViewRoot.java:979)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1779)
        at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:411)
        at org.apache.myfaces.trinidadinternal.application.ViewDeclarationLanguageFactoryImpl$ChangeApplyingVDLWrapper.renderView(ViewDeclarationLanguageFactoryImpl.java:354)
        at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:124)
        at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:286)
        at org.apache.myfaces.trinidadinternal.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:165)
        at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
        at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
        at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
        at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:724)

Sep 27, 2014 5:01:02 PM org.apache.myfaces.trinidadinternal.context.PartialViewContextImpl getPartialResponseWriter
WARNING: getPartialResponseWriter() called during render_reponse. The returned writer is not integrated with PPRResponseWriter