title: ng-style's variable not updating to the view
body: <p>I would like to add 20 px to my loader bar each time a successful request is completed.  a staggered set of data coming from various apis. $on each successful request, <strong>I would like to add 20 to <code>var progress</code></strong> unfortunally even tho the number is incrementing <code>$scope.progressWidth</code> will not update the view.  It stays static at <code>width: 0px</code>.  when i tried $scope.apply() it says digest is already happening.</p>
  
  <p>HTML view:</p>
  
  <pre><code>&lt;div class="loader" ng-style="progressWidth"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>js:</p>
  
  <pre><code>var progress = 0;
  
  $scope.progressWidth = {
      'width': progress + 'px'
  };
  
  angular.forEach(['load::1', 'load::2', 'load::3', 'load::video'], function (value) {
      $scope.$on(value, function (event) {
          load = true;
          loaded.push(true);
  
          if (load === true ) {
              load = false;
              progress += 20;
          }
  
          if (loaded[0] === true &amp;&amp; loaded[1] === true &amp;&amp; loaded[2] == true &amp;&amp; loaded[3]) {
              $scope.$broadcast('load::menu');
          }
      });
  });
  </code></pre>
  
  <p>data:</p>
  
  <pre><code>$http.jsonp('http://filltext.com/?rows=10&amp;delay=1&amp;fname={firstName}&amp;callback=JSON_CALLBACK').
          success(function(data){
              $scope.datas[0] = data;
              console.log($scope.datas);
              $scope.$emit('load::1');
      });
  
      $http.jsonp('http://filltext.com/?rows=10&amp;delay=2&amp;fname={firstName}&amp;callback=JSON_CALLBACK').
          success(function(data){
              $scope.datas[1] = data;
              console.log($scope.datas);
              $scope.$emit('load::2');
      });
  
      $http.jsonp('http://filltext.com/?rows=10&amp;delay=4&amp;fname={firstName}&amp;callback=JSON_CALLBACK').
          success(function(data){
              $scope.datas[2] = data;
              console.log($scope.datas);
              $scope.$emit('load::3');
      });
  </code></pre>