Time for action – adding callback parameters using RequestContext.addCallbackParam()

In this section, we will see how to add callback parameters to an AJAX response payload by performing the following steps:

1. Create a form with an input field and submit button using the following code:

   <h:form id="form1">
     <h:panelGrid columns="2">
       <h:outputLabel value="EmailId" />
       <p:inputText id="emailId" value="#{requestContextController.emailId}" required="true"/>
       
       <p:commandButton id="submitBtn" value="Submit" actionListener="#{requestContextController.handleSubmit}" 
       oncomplete="handleComplete(xhr, status, args)"/>
     </h:panelGrid>
     <h:outputText value="You have Entered : #{requestContextController.emailId}" />
   
   </h:form>

2. Implement the oncomplete callback JavaScript function handleComplete() as follows:

   <script type="text/javascript">  
     function handleComplete(xhr, status, args) 
     {  
       if(args.validationFailed) {
         alert...