title: how to call an element in another layer hbs
body: <p>There are two hbs files, one is under another layer, for example:</p>
  
  <p><code>testA.hbs</code> contains,</p>
  
  <pre><code>&lt;div&gt;
    {{/testB.hbs}} 
  &lt;/div&gt; 
  &lt;div id="area"&gt;
    Hello, world 
  &lt;/div&gt;
  </code></pre>
  
  <p>At <code>testB.js</code>, I want to call the id <code>area</code> which is presented at <code>testA.hbs</code>. How can I achieve this? </p>