How to update component with ajax when selecting a p:selectOneRadio? - ajax

Question

I'm trying to use ajax to update a component in my jsf page when selecting a radio button.
The managed bean is the following:
#SessionScoped
#ManagedBean
public class TestMB {
ArrayList<String> domande;
String[] risposte = new String[3];
public TestMB() {
domande = new ArrayList<String>();
domande.add("Domanda1");
domande.add("Domanda2");
domande.add("Domanda3");
}
public ArrayList<String> getDomande() {
return domande;
}
public void setDomande(ArrayList<String> domande) {
this.domande = domande;
}
public String[] getRisposte() {
return risposte;
}
public void setRisposte(String[] risposte) {
this.risposte = risposte;
}
public void asserta() {
System.out.println(risposte[0]);
}
}
The JSF page is this one:
<h:form id="label">
<p:panelGrid columns="1" layout="grid" styleClass="showcase-text-align-center">
<p:repeat var="domanda" value="#{testMB.domande}" varStatus="status">
<h1>#{domanda}</h1>
<p:selectOneRadio value="#{testMB.risposte[status.index]}">
<f:selectItem itemLabel="1" itemValue="1"></f:selectItem>
<f:selectItem itemLabel="2" itemValue="2"></f:selectItem>
<f:selectItem itemLabel="3" itemValue="3"></f:selectItem>
</p:selectOneRadio>
</p:repeat>
</p:panelGrid>
<p:outputLabel value="#{testMB.risposte[0]}"></p:outputLabel>
<p:commandButton update="label" value="Si" />
</h:form>>
I would like to update the form when I change option in the tag.
If I press the commandButton everything is ok but how to implement the same behavior in the radio button selection?
Thanks in advance!

Answer 1

You have the <p:ajax> component. Try something like this:
<p:selectOneRadio value="#{testMB.risposte[status.index]}">
<f:selectItem itemLabel="1" itemValue="1"></f:selectItem>
<f:selectItem itemLabel="2" itemValue="2"></f:selectItem>
<f:selectItem itemLabel="3" itemValue="3"></f:selectItem>
<p:ajax update="label" />
</p:selectOneRadio>