Share data between AngularJS controllers

Share data between AngularJS controllers

I’m trying to share data across controllers. Use-case is a multi-step form, data entered in one input is later used in multiple display locations outside the original controller. Code below and in jsfiddle here.
HTML



Input is : {{FirstName}}
Input should also be here: {{FirstName}}

JS
// declare the app with no dependencies
var myApp = angular.module(‘myApp’, []);

// make a factory to share data between controllers
myApp.factory(‘Data’, function(){
// I know this doesn’t work, but what will?
var FirstName = ”;
return FirstName;
});

// Step 1 Controller
myApp.controller(‘FirstCtrl’, function( $scope, Data ){

});

// Step 2 Controller
myApp.controller(‘SecondCtrl’, function( $scope, Data ){
$scope.FirstName = Data.FirstName;
});

Any help is greatly appreciated.

Solutions/Answers:

Solution 1:

A simple solution is to have your factory return an object and let your controllers work with a reference to the same object:

JS:

// declare the app with no dependencies
var myApp = angular.module('myApp', []);

// Create the factory that share the Fact
myApp.factory('Fact', function(){
  return { Field: '' };
});

// Two controllers sharing an object that has a string in it
myApp.controller('FirstCtrl', function( $scope, Fact ){
  $scope.Alpha = Fact;
});

myApp.controller('SecondCtrl', function( $scope, Fact ){
  $scope.Beta = Fact;
});

HTML:

<div ng-controller="FirstCtrl">
    <input type="text" ng-model="Alpha.Field">
    First {{Alpha.Field}}
</div>

<div ng-controller="SecondCtrl">
<input type="text" ng-model="Beta.Field">
    Second {{Beta.Field}}
</div>

Demo: http://jsfiddle.net/HEdJF/

When applications get larger, more complex and harder to test you might not want to expose the entire object from the factory this way, but instead give limited access for example via getters and setters:

myApp.factory('Data', function () {

    var data = {
        FirstName: ''
    };

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

With this approach it is up to the consuming controllers to update the factory with new values, and to watch for changes to get them:

myApp.controller('FirstCtrl', function ($scope, Data) {

    $scope.firstName = '';

    $scope.$watch('firstName', function (newValue, oldValue) {
        if (newValue !== oldValue) Data.setFirstName(newValue);
    });
});

myApp.controller('SecondCtrl', function ($scope, Data) {

    $scope.$watch(function () { return Data.getFirstName(); }, function (newValue, oldValue) {
        if (newValue !== oldValue) $scope.firstName = newValue;
    });
});

HTML:

<div ng-controller="FirstCtrl">
  <input type="text" ng-model="firstName">
  <br>Input is : <strong>{{firstName}}</strong>
</div>
<hr>
<div ng-controller="SecondCtrl">
  Input should also be here: {{firstName}}
</div>

Demo: http://jsfiddle.net/27mk1n1o/

Solution 2:

I prefer not to use $watch for this. Instead of assigning the entire service to a controller’s scope you can assign just the data.

JS:

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

myApp.factory('MyService', function(){
  return {
    data: {
      firstName: '',
      lastName: ''
    }
    // Other methods or objects can go here
  };
});

myApp.controller('FirstCtrl', function($scope, MyService){
  $scope.data = MyService.data;
});

myApp.controller('SecondCtrl', function($scope, MyService){
   $scope.data = MyService.data;
});

HTML:

<div ng-controller="FirstCtrl">
  <input type="text" ng-model="data.firstName">
  <br>Input is : <strong>{{data.firstName}}</strong>
</div>
<hr>
<div ng-controller="SecondCtrl">
  Input should also be here: {{data.firstName}}
</div>

Alternatively you can update the service data with a direct method.

JS: 

// A new factory with an update method
myApp.factory('MyService', function(){
  return {
    data: {
      firstName: '',
      lastName: ''
    },
    update: function(first, last) {
      // Improve this method as needed
      this.data.firstName = first;
      this.data.lastName = last;
    }
  };
});

// Your controller can use the service's update method
myApp.controller('SecondCtrl', function($scope, MyService){
   $scope.data = MyService.data;

   $scope.updateData = function(first, last) {
     MyService.update(first, last);
   }
});

Solution 3:

There are many ways you can share the data between controllers

  1. using services
  2. using $state.go services
  3. using stateparams
  4. using rootscope

Explanation of each method:

  1. I am not going to explain as its already explained by someone

  2. using $state.go

      $state.go('book.name', {Name: 'XYZ'}); 

  // then get parameter out of URL
  $state.params.Name;

  3. $stateparam works in a similar way to $state.go, you pass it as object from sender controller and collect in receiver controller using stateparam

  4. using $rootscope

    (a) sending data from child to parent controller

      $scope.Save(Obj,function(data) {
      $scope.$emit('savedata',data); 
      //pass the data as the second parameter
  });

  $scope.$on('savedata',function(event,data) {
      //receive the data as second parameter
  });

    (b) sending data from parent to child controller

      $scope.SaveDB(Obj,function(data){
      $scope.$broadcast('savedata',data);
  });

  $scope.SaveDB(Obj,function(data){`enter code here`
      $rootScope.$broadcast('saveCallback',data);
  });

Solution 4:

I’ve created a factory that controls shared scope between route path’s pattern, so you can maintain the shared data just when users are navigating in the same route parent path.

.controller('CadastroController', ['$scope', 'RouteSharedScope',
    function($scope, routeSharedScope) {
      var customerScope = routeSharedScope.scopeFor('/Customer');
      //var indexScope = routeSharedScope.scopeFor('/');
    }
 ])

So, if the user goes to another route path, for example ‘/Support’, the shared data for path ‘/Customer’ will be automatically destroyed. But, if instead of this the user goes to ‘child’ paths, like ‘/Customer/1’ or ‘/Customer/list’ the the scope won’t be destroyed.

You can see an sample here: http://plnkr.co/edit/OL8of9

Solution 5:

There are multiple ways to share data between controllers

  • Angular services
  • $broadcast, $emit method
  • Parent to child controller communication
  • $rootscope

As we know $rootscope is not preferable way for data transfer or communication because it is a global scope which is available for entire application

For data sharing between Angular Js controllers Angular services are best practices eg. .factory, .service
For reference

In case of data transfer from parent to child controller you can directly access parent data in child controller through $scope
If you are using ui-router then you can use $stateParmas to pass url parameters like id, name, key, etc

$broadcast is also good way to transfer data between controllers from parent to child and $emit to transfer data from child to parent controllers

HTML

<div ng-controller="FirstCtrl">
   <input type="text" ng-model="FirstName">
   <br>Input is : <strong>{{FirstName}}</strong>
</div>

<hr>

<div ng-controller="SecondCtrl">
   Input should also be here: {{FirstName}}
</div>

JS

myApp.controller('FirstCtrl', function( $rootScope, Data ){
    $rootScope.$broadcast('myData', {'FirstName': 'Peter'})
});

myApp.controller('SecondCtrl', function( $rootScope, Data ){
    $rootScope.$on('myData', function(event, data) {
       $scope.FirstName = data;
       console.log(data); // Check in console how data is coming
    });
});

Refer given link to know more about $broadcast

Solution 6:

Simplest Solution:

I have used an AngularJS service.

Step1: I have created an AngularJS service named SharedDataService.

myApp.service('SharedDataService', function () {
     var Person = {
        name: ''

    };
    return Person;
});

Step2: Create two controllers and use the above created service.

//First Controller
myApp.controller("FirstCtrl", ['$scope', 'SharedDataService',
   function ($scope, SharedDataService) {
   $scope.Person = SharedDataService;
   }]);

//Second Controller
myApp.controller("SecondCtrl", ['$scope', 'SharedDataService',
   function ($scope, SharedDataService) {
   $scope.Person = SharedDataService;
   }]);

Step3: Simply use the created controllers in the view.

<body ng-app="myApp">

<div ng-controller="FirstCtrl">
<input type="text" ng-model="Person.name">
<br>Input is : <strong>{{Person.name}}</strong>
</div>

<hr>

<div ng-controller="SecondCtrl">
Input should also be here: {{Person.name}}
</div>

</body>

To see working solution to this problem please press the link below

https://codepen.io/wins/pen/bmoYLr

.html file: 

<!DOCTYPE html>
<html>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script>

<body ng-app="myApp">

  <div ng-controller="FirstCtrl">
    <input type="text" ng-model="Person.name">
    <br>Input is : <strong>{{Person.name}}</strong>
   </div>

<hr>

  <div ng-controller="SecondCtrl">
    Input should also be here: {{Person.name}}
  </div>

//Script starts from here

<script>

var myApp = angular.module("myApp",[]);
//create SharedDataService
myApp.service('SharedDataService', function () {
     var Person = {
        name: ''

    };
    return Person;
});

//First Controller
myApp.controller("FirstCtrl", ['$scope', 'SharedDataService',
    function ($scope, SharedDataService) {
    $scope.Person = SharedDataService;
    }]);

//Second Controller
myApp.controller("SecondCtrl", ['$scope', 'SharedDataService',
    function ($scope, SharedDataService) {
    $scope.Person = SharedDataService;
}]);

</script>


</body>
</html>