title: dijit.byId return undefined
body: <p>It's very strange, I call dijit.byId() in dojo.addOnLoad(function{...}), it return undefined. In order to check if the id exist, i call dojo.byId() at the same time, it return some object. So I guess the component is not a dijit component? this is the whole code: Please help me, thanks in advice!</p>
  
  <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"&gt;
  &lt;html&gt;
  &lt;head&gt;
  &lt;meta http-equiv="Content-Type" content="text/html; charset=UTF-8"&gt;
  &lt;title&gt;&lt;/title&gt;
  
  &lt;!-- Dojo/Diji definations --&gt;
  &lt;link href='../dojoroot/dijit/themes/tundra/tundra.css' type='text/css' rel='stylesheet'/&gt;
  &lt;link href='../dojoroot/dojo/resources/dojo.css' type='text/css' rel='stylesheet'/&gt;
  
  &lt;script type="text/javascript" src="../dojoroot/dojo/dojo.js" djConfig="parseOnLoad: true"&gt;&lt;/script&gt;
  
  
  &lt;!-- Main scripts --&gt;
  
  &lt;script type="text/javascript"&gt;
      dojo.addOnLoad(function()
      {
          // Include library
          dojo.require("dijit.layout.BorderContainer");
          dojo.require("dijit.layout.TabContainer");
          dojo.require("dijit.layout.ContentPane");
  
          // add the select child event to the tab panel
          alert(dijit.byId("contentTabPanel"));  // return no defined
          alert(dojo.byId("contentTabPanel")); // return an object
  
      });
  &lt;/script&gt;
  &lt;/head&gt;
  
  &lt;body class="tundra"&gt;
  &lt;div dojoType="dijit.layout.BorderContainer" style="width: 100%; height: 100%;"&gt;
      &lt;!-- Content Tab Panel --&gt;
      &lt;div id="contentTabPanel" dojoType="dijit.layout.TabContainer" region="center"&gt;
          &lt;!-- Tab UserGroup --&gt;
          &lt;div dojoType="dijit.layout.ContentPane" title="UserGroup"&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>OMFG!!!!! I know the reason!!!!! I cost 5 Hours just for this STUPID error:</p>
  
  <p>I MUST write the  </p>
  
  <pre><code>    // Include library
      dojo.require("dijit.layout.BorderContainer");
      dojo.require("dijit.layout.TabContainer");
      dojo.require("dijit.layout.ContentPane");
  </code></pre>
  
  <p>outside the dojo.addOnLoad(function() { !!!</p>