AngularJS access parent scope from child controller

Question

I\'ve set up my controllers using data-ng-controller=\"xyzController as vm\"

I have a scenario with parent / child nested controllers. I have no problem

Answer 1

When you are using as syntax, like ParentController as parentCtrl, to define a controller then to access parent scope variable in child controller use following :

var id = $scope.parentCtrl.id;

Where parentCtrl is name of parent controller using as syntax and id is a variable defined in same controller.

Answer 2

From a child component you can access the properties and methods of the parent component with 'require'. Here is an example:

Parent:

.component('myParent', mymodule.MyParentComponent)
...
controllerAs: 'vm',
...
var vm = this;
vm.parentProperty = 'hello from parent';

Child:

require: {
    myParentCtrl: '^myParent'
},
controllerAs: 'vm',
...
var vm = this;
vm.myParentCtrl.parentProperty = 'hello from child';

Answer 3

If your HTML is like below you could do something like this:

<div ng-controller="ParentCtrl">
    <div ng-controller="ChildCtrl">
    </div>
</div>

Then you can access the parent scope as follows

function ParentCtrl($scope) {
    $scope.cities = ["NY", "Amsterdam", "Barcelona"];
}

function ChildCtrl($scope) {
    $scope.parentcities = $scope.$parent.cities;
}

If you want to access a parent controller from your view you have to do something like this:

<div ng-controller="xyzController as vm">
   {{$parent.property}}
</div>

See jsFiddle: http://jsfiddle.net/2r728/

Update

Actually since you defined cities in the parent controller your child controller will inherit all scope variables. So theoritically you don't have to call $parent. The above example can also be written as follows:

function ParentCtrl($scope) {
    $scope.cities = ["NY","Amsterdam","Barcelona"];
}

function ChildCtrl($scope) {
    $scope.parentCities = $scope.cities;
}

The AngularJS docs use this approach, here you can read more about the $scope.

Another update

I think this is a better answer to the original poster.

HTML

<div ng-app ng-controller="ParentCtrl as pc">
    <div ng-controller="ChildCtrl as cc">
        <pre>{{cc.parentCities | json}}</pre>
        <pre>{{pc.cities | json}}</pre>
    </div>
</div>

JS

function ParentCtrl() {
    var vm = this;
    vm.cities = ["NY", "Amsterdam", "Barcelona"];
}

function ChildCtrl() {
    var vm = this;
    ParentCtrl.apply(vm, arguments); // Inherit parent control

    vm.parentCities = vm.cities;
}

If you use the controller as method you can also access the parent scope as follows

function ChildCtrl($scope) {
    var vm = this;
    vm.parentCities = $scope.pc.cities; // note pc is a reference to the "ParentCtrl as pc"
}

As you can see there are many different ways in accessing $scopes.

Updated fiddle

function ParentCtrl() {
    var vm = this;
    vm.cities = ["NY", "Amsterdam", "Barcelona"];
}
    
function ChildCtrl($scope) {
    var vm = this;
    ParentCtrl.apply(vm, arguments);
    
    vm.parentCitiesByScope = $scope.pc.cities;
    vm.parentCities = vm.cities;
}
    

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.20/angular.min.js"></script>
<div ng-app ng-controller="ParentCtrl as pc">
  <div ng-controller="ChildCtrl as cc">
    <pre>{{cc.parentCities | json}}</pre>
    <pre>{{cc.parentCitiesByScope | json }}</pre>
    <pre>{{pc.cities | json}}</pre>
  </div>
</div>