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angularjs: broadcast from directive to controller
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Solved angularjsangularjs-scopedom-eventsangularjs-components
G

3

13

Im trying to send a message from within a directive to its parent controller (without success)

Here is my HTML

<div ng-controller="Ctrl">
   <my-elem/>
</div>

Here is the code in the controller which listens for the event

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

And finally the directive looks like

angular.module('App').directive('myElem',
   function () {
    return {
        restrict: 'E',
        templateUrl: '/views/my-elem.html',
        link: function ($scope, $element, $attrs) {
            $element.on('click', function() {
                  console.log("We're in") ; 
                  $scope.$emit('go', { nr: 10 }) ;
            }
        }
    }
  }) ;

I've tried different scope configuration and $broadcast instead of $emit. I see that the event gets fired, but the controller does not receive a 'go' event. Any suggestions ?

Gangling answered 25/9, 2013 at 10:11 Comment(2)
Did you use $scope.$on('go', function(){ .... }); or is that a typo? – Dexterdexterity
This approach for communication of events is dated. See AngularJS Developer Guide - Component-based application architecture. – Jovia
M
26

There is no method on with scope. In angular it's $on

below should work for you 

<!doctype html>
<html ng-app="test">
  <head>
    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0-rc.2/angular.js"></script>

  </head>
 <body ng-controller="test" >    
 <my-elem/>

<!-- tabs -->


 <script>
     var app = angular.module('test', []);
     app.controller('test', function ($scope) {

         $scope.$on('go', function () { alert('event is clicked') });
     });
     app.directive('myElem',
   function () {
       return {
           restrict: 'E',
           replace:true,
           template: '<div><input type="button" value=check/></input>',
           link: function ($scope, $element, $attrs) {
               alert("123");
               $element.bind('click', function () {
                   console.log("We're in");
                   $scope.$emit('go');
               });
               }
       }
   }) ;

   </script>
</body>


</html>
Maillol answered 25/9, 2013 at 10:25 Comment(1)
The closing tag </input> is bad HTML. – Jovia
H
2

To get { nr: 10 } you should add 2 arguments to listener: event and data:

$scope.$on('go', function(event, data){ 
  alert(JSON.stringify(data));
});

(keep in mind that we use $on and not on)

Full example in plunker

Hadlee answered 7/8, 2018 at 10:55 Comment(0)
J
1

$broadcast, $emit, and $on are deprecated

Use of the scope/rootScope event bus is deprecated and will make migration to Angular 2+ more difficult.

To facilitate making the transition to Angular 2+ easier, AngularJS 1.5 introduced components:

app.component("myElem", {
    bindings: {
      onGo: '&',
    },
    template: `
        <button ng-click="$ctrl.go($event,{nr:10})">
            Click to GO
        </button>
    `,
    controller: function() {
        this.go = (event,data) => {
            this.onGo({$event: event, $data: data});
        };
    }
});

Usage:

<div ng-controller="Ctrl as $ctrl">
   <my-elem on-go="$ctrl.fn($data)></my-elem>
</div>

The component uses an attribute with AngularJS expression (&) binding that invokes a function in the parent controller. Instead of clogging the scope/rootScope event bus with numerous events, the event goes directly to the function that uses it.

The DEMO

angular.module('app', [])
.controller ('Ctrl', function () {
    this.go = (data) => {
      console.log(data);
      this.update = data;
    };
})
.component("myElem", {
    bindings: {
      onGo: '&',
    },
    template: `
      <fieldset>
        <input ng-model="$ctrl.nr" /><br>
        <button ng-click="$ctrl.go($event,$ctrl.nr)">
            Click to Update
        </button>
      </fieldset>
    `,
    controller: function() {
        this.nr = 10;
        this.go = (event,data) => {
            this.onGo({$event: event, $data: data});
        };
    }
})
<script  src="//unpkg.com/angular/angular.js"></script>
<body ng-app="app" ng-controller="Ctrl as $ctrl">
    <p>update={{$ctrl.update}}</p>
    <my-elem on-go="$ctrl.go($data)"></my-elem>
</body>

For more information, see

Jovia answered 4/8, 2018 at 16:12 Comment(0)

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