title: reRender and rendered attribute in visualforce
body: <p>i write a visualforce page with source code</p>
  
  <pre><code>&lt;apex:page controller="MyController1"&gt;
  &lt;apex:form&gt;
  &lt;apex:pageBlock &gt;
  &lt;apex:pageBlockSection  id="search"&gt;
  &lt;apex:commandLink action="{!commandLinkAction}" value="Advance Search"  reRender="thePanel" id="theCommandLink"/&gt;
  &lt;apex:outputPanel id="thePanelWrapper"&gt;
  &lt;apex:outputPanel id="thePanel" rendered="{! rend}" layout="block"&gt;My div&lt;/apex:outputPanel&gt;
  &lt;/apex:outputPanel&gt;
  &lt;/apex:pageBlockSection&gt;
  &lt;/apex:pageBlock&gt;
  &lt;/apex:form&gt;
  &lt;/apex:page&gt;
  </code></pre>
  
  <p>and the MyController1 class is </p>
  
  <pre><code>public class MyController1{
  public Boolean rend{get;set;}
  public PageReference commandLinkAction(){
  rend=true;
  return null;
  }
  
  }
  </code></pre>
  
  <p>when i click on Advanced Search link nothing happens but i was expecting outputPanel with id "thePanel" should render.why it is not rendering please someone explain??</p>