title: ng-class conditional value not getting reflected
body: <p>I have a list. I want to show the selected object as active. For that I have written the code as below:</p>
  
  <p><strong>HTML</strong></p>
  
  <pre><code>&lt;li ng-class="{'active' : testObject.selected}" &gt;
      &lt;a ng-click="showApp()"&gt;                
          &lt;span&gt;App&lt;/span&gt;
      &lt;/a&gt;
  &lt;/li&gt;
  </code></pre>
  
  <p><strong>Controller</strong></p>
  
  <pre><code>$scope.testObject = {
      selected: false
  };
  
  $scope.showApp = function() {  
     $scope.testObject['selected'] = true;
     //my code
  }
  </code></pre>
  
  <p>Here, <code>testObject.selected</code> is a boolean and I am setting its value (true/false) inside <code>showApp()</code> function. It is not working somehow.</p>