Angularjs $broadcast once, $on twice

Question

It sends $broadcast once from the rootScope, but the listener ($on) gets called twice.

The listener is in a controller and it uses $rootScope.$on instead of $scope.$on. Has someone had this problem?

edit

rootScope:

$rootScope.$broadcast('menuActivateAction' + item.event_name_postfix, item.event_args);

other Controller:

$rootScope.$on('menuActivateActionPublish', function(event) {});

Bluebill

you should provide your code – Acima

Maybe you have two controllers? – Gastrocnemius

Probably you have to remove the listener when the controller is destroyed. I'd even register the listener in the .run phase and not in the controller - to avoid auch problems the controller should only register listener on is own scope – Vary

Possible duplicate of AngularJs broadcast repeating execution too many times – Bay

Answer 1

Since you register your $on listener on $rootScope, it doesn't get destroyed with the controller and next time you init the controller it gets created again.

You should create your listener on controller scope

$scope.$on('menuActivateActionPublish', function(event) {});

Semiaquatic

Hey in my case on listen called incrementally. – Weakfish

@UmairKhanzada sorry I dont understand that comment – Semiaquatic

listen $rootScope.$broadcast('xyz'); event when user login and when user logout and login again it'll be listen incrementally. listen function $rootScope.$on('xyz', function(){ console.log('running')}); – Weakfish

It depends on where do you have $broadcast and $on . In your case, you should have $broadcast() in function that handles login - wherever you determine that user is logged in, and $on() only in single place. For example app.run(). That is if you want to use $rootScope. If you want to use it in controllers or other "modules" then use $scope.$on() and as many times you want, because it gets destroyed – Semiaquatic

Answer 2

Be careful you avoid two instances of the controller means two event listeners, which means the method gets executed twice !! ( example: using twice 'ng-controller' )

Footloose

Answer 3

To complement que1326 answer, as an example, if you are using ui-router and have something like

.state('app.yourpage', {
            url:'yourPage',
            views: {
                'content@': {
                    templateUrl : 'views/yourPage.html',
                    controller  : 'YourController'
                }
            }
        })

and in yourPage.html you have a ng-controller="YourController as Ctrl", then you are creating 2 instances of the controller: 1 instance is created by the state configuration and another one in your html.

Musick

Answer 4

The only solution I could get to work was to create the listener inside the $viewContentLoaded event:

$scope.$on('$viewContentLoaded', function() {
  //Put your listener(s) in here
  $scope.$on('menuActivateActionPublish', function(event) {});
});

Thanksgiving