How can I pass some data from one controller to another peer controller [duplicate]

I have the following two peer controllers. There's no parent to these:

<div data-ng-controller="Controller1">

</div>

<div data-ng-controller="Controller2">
   The value of xxx is: {{ xxx }}
</div>

angular.module('test')
   .controller('QuestionsStatusController1',
    ['$rootScope', '$scope'
    function ($rootScope, $scope) {
    // How can I set the value of xxx in the HTML that's part of Controller2    
    }]);

angular.module('test')
   .controller('QuestionsStatusController2',
    ['$rootScope', '$scope',
    function ($rootScope, $scope) {
    }]);

In controller 1 I want to update the value of the variable xxx in the HTML that's controlled by Controller2. Is there a way I can do this?

Solution 1:

Use a service to achieve this:

MyApp.app.service("xxxSvc", function () {

var _xxx = {};

return {
    getXxx: function () {
        return _xxx;
    },
    setXxx: function (value) {
        _xxx = value;
    }
};

});

Next, inject this service into both controllers.

In Controller1, you would need to set the shared xxx value with a call to the service: xxxSvc.setXxx(xxx)

Finally, in Controller2, add a $watch on this service's getXxx() function like so:

  $scope.$watch(function () { return xxxSvc.getXxx(); }, function (newValue, oldValue) {
        if (newValue != null) {
            //update Controller2's xxx value
            $scope.xxx= newValue;
        }
    }, true);

Solution 2:

Definitely use a service to share data between controllers, here is a working example. $broadcast is not the way to go, you should avoid using the eventing system when there is a more appropriate way. Use a 'service', 'value' or 'constant' (for global constants).

http://plnkr.co/edit/ETWU7d0O8Kaz6qpFP5Hp

Here is an example with an input so you can see the data mirror on the page: http://plnkr.co/edit/DbBp60AgfbmGpgvwtnpU

var testModule = angular.module('testmodule', []);

testModule
   .controller('QuestionsStatusController1',
    ['$rootScope', '$scope', 'myservice',
    function ($rootScope, $scope, myservice) {
       $scope.myservice = myservice;   
    }]);

testModule
   .controller('QuestionsStatusController2',
    ['$rootScope', '$scope', 'myservice',
    function ($rootScope, $scope, myservice) {
      $scope.myservice = myservice;
    }]);

testModule
    .service('myservice', function() {
      this.xxx = "yyy";
    });