title: p:blockUI / pe:blockUI: Why doesn't it work in my simple example?
body: <p><strong>I would like to hide an element while a button triggered action is being performed:</strong></p>
  
  <pre><code>&lt;h:form id="sendtxform"&gt;
          &lt;p:panelGrid columns="1" styleClass="ui-noborder"&gt;      
              &lt;pe:blockUI block="input" widgetVar="blockUIWidget"&gt;
              LOADING&lt;br /&gt;
                  &lt;p:graphicImage name="images/ajax-loader.gif" /&gt;
              &lt;/pe:blockUI&gt;
  
              &lt;p:commandButton id="command" value="ISSUE APP"
                  actionListener="#{transactionXmlController.getTxDataPredefined}"
                  ajax="true" update="growl,input"
                  onstart="PF('blockUIWidget').block();"
                  oncomplete="PF('blockUIWidget').unblock();"&gt;
              &lt;/p:commandButton&gt;
  
              &lt;p:inputTextarea id="input" cols="150" rows="30" autoResize="false"
                  value="#{transactionXmlEditableModel.xml}" /&gt;
          &lt;/p:panelGrid&gt;
      &lt;/h:form&gt;
  </code></pre>
  
  <p>I tried with p:blockUI / pe:blockUI and with/without the onstart and oncomplete attributes.</p>
  
  <p>What am I doig wrong ? I use blockUI somewhere else, and it is working fine:
  
  The only difference is that the table is its own trigger.</p>
  
  <p>I followed <a href="http://www.journaldev.com/3413/primefaces-blockui-component-example-tutorial" rel="nofollow">this</a> tutorial.</p>