TabContainer doesn't show tab in my page

I am doing RTC(3.0.1.3) extension development. I copy below code from http://dojotoolkit.org/reference-guide/1.7/dijit/layout/TabContainer.html#dijit-layout-tabcontainer to my HTML template file.
<div style="width: 350px; height: 300px">
     <div data-dojo-type="dijit.layout.TabContainer" style="width: 100%; height: 100%;">
         <div data-dojo-type="dijit.layout.ContentPane" title="My first tab" selected="true">
             Lorem ipsum and all around...
         </div>
         <div data-dojo-type="dijit.layout.ContentPane" title="My second tab">
             Lorem ipsum and all around - second...
         </div>
         <div data-dojo-type="dijit.layout.ContentPane" title="My last tab" closable="true">
             Lorem ipsum and all around - last...
         </div>
     </div>
 /div>

And I have added below to my js file.
    dojo.require("dojo.parser");
    dojo.require("dijit.layout.TabContainer");
    dojo.require("dijit.layout.ContentPane");

    widgetsInTemplate:true,

But the tab doesn't show as the example does. Other declarive widgets in HTML can work well except TabConainer. Anyone could help me about this. Thank you very much!