How to apply delay on AngularJS

Just inject $timeout in your controller and use this.

$timeout(function() { $scope.displayErrorMsg = false;}, 2000);

Also you can use $digest or $apply as below

setTimeout(function() {
    $scope.displayErrorMsg = false;
    $scope.$digest();
}, 2000);

setTimeout(function () {
  $scope.$apply(function(){
      $scope.displayErrorMsg = false;
  });
}, 2000);

Check here how these works,

http://www.sitepoint.com/understanding-angulars-apply-digest/