How to pass data between controllers in angularjs?

Question

Angular

There are several controllers in Angular.
How can I access the value/function of another from rootScop or from one controller?
- - - -
myApp.controller('AdminController', function($scope,$http,$rootScope) {
$scope.get_data= function () {
alert("I'm from AdminController");
}
$scope.get_data_in_SettingsController= function ( ) {
//how do I refer to SettingsController here?
}
}
myApp.controller('SettingsController', function($scope,$http,$rootScope) {
$scope.get_data= function () {
alert("I'm from SettingsController") ;
}
}

Answer 1

Use factories.

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

// make a factory to share data between controllers
myApp.factory('Data', function(){
  var data = {
    firstName: ''
  };

  return {
    getFirstName: function () {
      return data.firstName;
    },
    setFirstName: function (firstName) {
      data.firstName = firstName;
    }
  };
});