How to access parent scope from within a custom directive *with own scope* in AngularJS?

angularjs angularjs-directive

See What are the nuances of scope prototypal / prototypical inheritance in AngularJS?

To summarize: the way a directive accesses its parent ($parent) scope depends on the type of scope the directive creates:

  1. default (scope: false) - the directive does not create a new scope, so there is no inheritance here. The directive's scope is the same scope as the parent/container. In the link function, use the first parameter (typically scope).

  2. scope: true - the directive creates a new child scope that prototypically inherits from the parent scope. Properties that are defined on the parent scope are available to the directive scope (because of prototypal inheritance). Just beware of writing to a primitive scope property -- that will create a new property on the directive scope (that hides/shadows the parent scope property of the same name).

  3. scope: { ... } - the directive creates a new isolate/isolated scope. It does not prototypically inherit the parent scope. You can still access the parent scope using $parent, but this is not normally recommended. Instead, you should specify which parent scope properties (and/or function) the directive needs via additional attributes on the same element where the directive is used, using the =, @, and & notation.

  4. transclude: true - the directive creates a new "transcluded" child scope, which prototypically inherits from the parent scope. If the directive also creates an isolate scope, the transcluded and the isolate scopes are siblings. The $parent property of each scope references the same parent scope.
    Angular v1.3 update: If the directive also creates an isolate scope, the transcluded scope is now a child of the isolate scope. The transcluded and isolate scopes are no longer siblings. The $parent property of the transcluded scope now references the isolate scope.

The above link has examples and pictures of all 4 types.

You cannot access the scope in the directive's compile function (as mentioned here: https://github.com/angular/angular.js/wiki/Dev-Guide:-Understanding-Directives). You can access the directive's scope in the link function.

Watching:

For 1. and 2. above: normally you specify which parent property the directive needs via an attribute, then $watch it:

<div my-dir attr1="prop1"></div>

scope.$watch(attrs.attr1, function() { ... });

If you are watching an object property, you'll need to use $parse:

<div my-dir attr2="obj.prop2"></div>

var model = $parse(attrs.attr2);
scope.$watch(model, function() { ... });

For 3. above (isolate scope), watch the name you give the directive property using the @ or = notation:

<div my-dir attr3="{{prop3}}" attr4="obj.prop4"></div>

scope: {
  localName3: '@attr3',
  attr4:      '='  // here, using the same name as the attribute
},
link: function(scope, element, attrs) {
   scope.$watch('localName3', function() { ... });
   scope.$watch('attr4',      function() { ... });

Accessing controller method means accessing a method on parent scope from directive controller/link/scope.

If the directive is sharing/inheriting the parent scope then it is quite straight forward to just invoke a parent scope method.

Little more work is required when you want to access parent scope method from Isolated directive scope.

There are few options (may be more than listed below) to invoke a parent scope method from isolated directives scope or watch parent scope variables (option#6 specially).

Note that I used link function in these examples but you can use a directive controller as well based on requirement.

Option#1. Through Object literal and from directive html template

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged(selectedItems)" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" ng-change="selectedItemsChanged({selectedItems:selectedItems})" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]

});

working plnkr: http://plnkr.co/edit/rgKUsYGDo9O3tewL6xgr?p=preview

Option#2. Through Object literal and from directive link/scope

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged(selectedItems)" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-change="selectedItemsChangedDir()" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html",
    link: function (scope, element, attrs){
      scope.selectedItemsChangedDir = function(){
        scope.selectedItemsChanged({selectedItems:scope.selectedItems});  
      }
    }
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

working plnkr: http://plnkr.co/edit/BRvYm2SpSpBK9uxNIcTa?p=preview

Option#3. Through Function reference and from directive html template

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-change="selectedItemsChanged()(selectedItems)" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems:'=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

working plnkr: http://plnkr.co/edit/Jo6FcYfVXCCg3vH42BIz?p=preview

Option#4. Through Function reference and from directive link/scope

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter selected-items="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItemsReturnedFromDirective}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" ng-change="selectedItemsChangedDir()" ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=',
      selectedItemsChanged: '&'
    },
    templateUrl: "itemfilterTemplate.html",
    link: function (scope, element, attrs){
      scope.selectedItemsChangedDir = function(){
        scope.selectedItemsChanged()(scope.selectedItems);  
      }
    }
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.selectedItemsChanged = function(selectedItems1) {
    $scope.selectedItemsReturnedFromDirective = selectedItems1;
  }

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]

});

working plnkr: http://plnkr.co/edit/BSqx2J1yCY86IJwAnQF1?p=preview

Option#5: Through ng-model and two way binding, you can update parent scope variables.. So, you may not require to invoke parent scope functions in some cases.

index.html

<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>

    <p> Directive Content</p>
    <sd-items-filter ng-model="selectedItems" selected-items-changed="selectedItemsChanged" items="items"> </sd-items-filter>


    <P style="color:red">Selected Items (in parent controller) set to: {{selectedItems}} </p>

  </body>

</html>

itemfilterTemplate.html

<select ng-model="selectedItems" multiple="multiple" style="height: 200px; width: 250px;" 
 ng-options="item.id as item.name group by item.model for item in items | orderBy:'name'">
  <option>--</option>
</select>

app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      items: '=',
      selectedItems: '=ngModel'
    },
    templateUrl: "itemfilterTemplate.html"
  }
})

app.controller('MainCtrl', function($scope) {
  $scope.name = 'TARS';

  $scope.selectedItems = ["allItems"];

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
    }]
});

working plnkr: http://plnkr.co/edit/hNui3xgzdTnfcdzljihY?p=preview

Option#6: Through $watch and $watchCollection It is two way binding for items in all above examples, if items are modified in parent scope, items in directive would also reflect the changes.

If you want to watch other attributes or objects from parent scope, you can do that using $watch and $watchCollection as given below

html

<!DOCTYPE html>
<html ng-app="plunker">

<head>
  <meta charset="utf-8" />
  <title>AngularJS Plunker</title>
  <script>
    document.write('<base href="' + document.location + '" />');
  </script>
  <link rel="stylesheet" href="style.css" />
  <script data-require="[email protected]" src="https://code.angularjs.org/1.3.9/angular.js" data-semver="1.3.9"></script>
  <script src="app.js"></script>
</head>

<body ng-controller="MainCtrl">
  <p>Hello {{user}}!</p>
  <p>directive is watching name and current item</p>
  <table>
    <tr>
      <td>Id:</td>
      <td>
        <input type="text" ng-model="id" />
      </td>
    </tr>
    <tr>
      <td>Name:</td>
      <td>
        <input type="text" ng-model="name" />
      </td>
    </tr>
    <tr>
      <td>Model:</td>
      <td>
        <input type="text" ng-model="model" />
      </td>
    </tr>
  </table>

  <button style="margin-left:50px" type="buttun" ng-click="addItem()">Add Item</button>

  <p>Directive Contents</p>
  <sd-items-filter ng-model="selectedItems" current-item="currentItem" name="{{name}}" selected-items-changed="selectedItemsChanged" items="items"></sd-items-filter>

  <P style="color:red">Selected Items (in parent controller) set to: {{selectedItems}}</p>
</body>

</html>

script app.js

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

app.directive('sdItemsFilter', function() {
  return {
    restrict: 'E',
    scope: {
      name: '@',
      currentItem: '=',
      items: '=',
      selectedItems: '=ngModel'
    },
    template: '<select ng-model="selectedItems" multiple="multiple" style="height: 140px; width: 250px;"' +
      'ng-options="item.id as item.name group by item.model for item in items | orderBy:\'name\'">' +
      '<option>--</option> </select>',
    link: function(scope, element, attrs) {
      scope.$watchCollection('currentItem', function() {
        console.log(JSON.stringify(scope.currentItem));
      });
      scope.$watch('name', function() {
        console.log(JSON.stringify(scope.name));
      });
    }
  }
})

 app.controller('MainCtrl', function($scope) {
  $scope.user = 'World';

  $scope.addItem = function() {
    $scope.items.push({
      id: $scope.id,
      name: $scope.name,
      model: $scope.model
    });
    $scope.currentItem = {};
    $scope.currentItem.id = $scope.id;
    $scope.currentItem.name = $scope.name;
    $scope.currentItem.model = $scope.model;
  }

  $scope.selectedItems = ["allItems"];

  $scope.items = [{
    "id": "allItems",
    "name": "All Items",
    "order": 0
  }, {
    "id": "CaseItem",
    "name": "Case Item",
    "model": "PredefinedModel"
  }, {
    "id": "Application",
    "name": "Application",
    "model": "Bank"
  }]
});

You can always refer AngularJs documentation for detailed explanations about directives.

Related

How to get the system uptime in Windows? [closed]
How do I compare version numbers in Python?
How do you find the first key in a dictionary?
iPhone App Icons - Exact Radius?
What is the difference between the "const" and "final" keywords in Dart?
Select all contents of textbox when it receives focus (Vanilla JS or jQuery)
Android XML Percent Symbol
How do I look inside a Python object?
Creating folders inside a GitHub repository without using Git
What's the use of ob_start() in php?
How to extract request http headers from a request using NodeJS connect
How to access the last value in a vector?