title: Angularjs ns-style change via Controller
body: <p>I am trying to change background color of div. Mine html code is below:</p>
  
  <pre><code>&lt;div ng-style="{'background-color': backgroundImageInfo}"&gt;
      &lt;input type="file" onchange="angular.element(this).scope().fileThatChangeBackground(this)" /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>Mine js code inside controller:</p>
  
  <pre><code>$scope.backgroundImageInfo='red';
  $scope.fileThatChangeBackground = function() {
      alert($scope.backgroundImageInfo);
      $scope.backgroundImageInfo='blue';
  };
  </code></pre>
  
  <p>First line of controller change background color to red. When i am set file to input alert show 'red' and did not change background color to blue. When i change file of input(fire function) alert show 'blue' and again did not change background color. Why ng-style dont change color when i change value from function?</p>