title: How to dynamically generate css class inside an each statement for an Ember View
body: <pre><code>  &lt;div&gt;
    {{#each value in controller}}
    &lt;div {{classNameBindings "col-lg-{{value}}"}}&gt;{{value}}&lt;/div&gt;
    {{/each}}
    &lt;/div&gt;
  </code></pre>
  
  <p>Above is my partial view. </p>
  
  <p>I want to generate classes like: col-lg-1, col-lg-2 etc
  My controller is:</p>
  
  <pre><code>App.circleController = Ember.ArrayController.extend({
      setupController: function(controller) {
          controller.set('content', [1,2,3,4,5,6,7]);
      }
  });
  </code></pre>
  
  <p>why I get error: assertion failed: an Ember.CollectionView's content must implement Ember.Array. ?</p>