how it not working add class using ng-repeat? :  it may be click photo and not add class inside the ng-repeat using angularjs

       <div class="resultitem" ng-repeat="a in vm.gettrustalbum">
        <div class="result">
         </div>
      </div>


  add class "demo" inside the ng-repeat?


   output

     <div class="resultitem" ng-repeat="a in vm.gettrustalbum">
         <div class="result demo">
         </div>
      </div>


 