Send data from controller to directive - angularjs

Question

I want to send that to my directive but I want that data to stay updated if the data in the controller changes.
// Controller
angular
.module('app')
.controller('IndexController', IndexController)
IndexController.$inject = [];
function IndexController() {
var vm = this;
vm.name = 'John';
newName = function() {
vm.name = 'Brian';
}
newName();
}
// Directive
angular
.module('app')
.directive('userName', userName);
userName.$inject = ['$document'];
function userName($document) {
var directive = {
restrict: 'EA',
template: '<div id="user"></div>',
replace: true,
scope: {
name: '='
},
link: function(scope, elem, attrs) {
console.log(scope.data);
}
}
return directive;
}
this is how I use the directive. the problem is that it always returns the first name and not the new name after the change in the controller.
<div ng-controller="indexController">
<user-name name="indexController.name">
</div>
thank you.

Answer 1

Try this, you just have to inject $scope into your Indexcontroller
angular
.module('app', [])
.controller('IndexController', function($scope) {
var vm = this;
vm.name = 'John';
vm.newName = function() {
vm.name = 'Brian';
console.log(vm.name);
}
//vm.newName();
})
.directive('userName', ['$document', function() {
var directive = {
restrict: 'E',
template: '<div id="user"></div>',
replace: true,
scope: {
name: '='
},
link: function(scope, elem, attrs) {
console.log(scope.name);
}
}
return directive;
}])
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="app" ng-controller="IndexController as vm">
<user-name name="vm.name"></user-name>
<button ng-click="vm.newName()">Click</button>
</div>

Answer 2

Without using as in controller, you cannot use controller.prop inside the scope.
Inside the controlleryou need to call the method using its $scope or this.
Check the below code.
angular
.module('app', [])
.controller('IndexController', function($scope) {
$scope.name = 'John';
$scope.newName = function() {
$scope.name = 'Brian';
}
$scope.newName();
})
.directive('userName', ['$document', function() {
var directive = {
restrict: 'E',
template: '<div id="user"></div>',
replace: true,
scope: {
name: '='
},
link: function(scope, elem, attrs) {
console.log(scope.name);
}
}
return directive;
}])
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="app" ng-controller="IndexController">
<user-name name="name"></user-name>
</div>