javascript - ng-show/ng-hide value is not changing after getting the data from firebase? -

when receiving data firebase changing scope of ng-show/ng-hide value false.but not affecting thing in view. scope value changing when clicked again have update value dynamically . please me sought out problem.

thanks in advance

here code

  <script>          var app = angular.module("myapp", []);          app.controller("redeemctrl", function($scope) {          $scope.showdiv = true;        $scope.redeemsubmit = function() {      firebase.database().ref().once('value', function(snapshot) {          $scope.user = snapshot.val()          console.log('getting data fire base' + json.stringify($scope.user));          $scope.showdiv = false;            });     }  }); </script> 

view

 <div ng-controller="redeemctrl">         <div ng-show="showdiv">             <form>                 <div>                     <input ng-model="coupon" type="text">                 </div>                  <div class="row">                     <button  ng-click="redeemsubmit()"  class="btn">submit</button>                 </div>             </form>         </div>         <div class="row" ng-hide="showdiv">             <h3>{{user}}</h3>         </div>     </div> 

just notice angular change has made:

   console.log('getting data fire base' + json.stringify($scope.user));    $scope.showdiv = false;    $scope.user = $scope.coupon;    $scope.$apply();