title: Angular ngStyle value change does not apply to the DOM
body: <p>For example:</p>
  
  <pre><code>&lt;ul id= "scroller" data-ng-style="{'width': {{competitors.length * 114}} + 'px'}"&gt;
  </code></pre>
  
  <p>At first competitors array have two elements, the width is <code>228px;</code> then the array has six elements, the width shown in <code>data-ng-style</code> is <code>668px</code>, but actually the width is still <code>228px</code>, why?</p>
  
  <pre><code>    app.controller('intelligenceController', ['$scope', '$http', function($scope,$http)  {
      $scope.competitors = [
          {
              "competitorId": "excellent",
          },
          {
              "competitorId": "average",
          }
      ];
      $scope.sumCompetitors = function(customList) {
          if (0 === customList.length) {
              $scope.competitors = $scope.competitors.concat({
                  "competitorId": "none",
              });
          } else {
              $scope.competitors = $scope.competitors.concat(customList);
          }
      };
      $http.get('./listCompetitors.json').success(function(competitorsList) {
          if (false === competitorsList.hasError &amp;&amp; 0 === competitorsList.content.code) {
              $scope.sumCompetitors(competitorsList.content.data);
          }
      });
  }]);
  </code></pre>