Call method in controller from directive - angularjs

Question

HTML :
<div id="idOfDiv" ng-show="ngShowName">
Hello
</div>
I would like to call the function which is declared in my controller from my directive.
How can I do this? I don't receive an error when I call the function but nothing appears.
This is my directive and controller :
var d3DemoApp = angular.module('d3DemoApp', []);
d3DemoApp.controller('mainController', function AppCtrl ($scope,$http, dataService,userService,meanService,multipartForm) {
$scope.testFunc = function(){
$scope.ngShowName = true;
}
});
d3DemoApp.directive('directiveName', [function($scope) {
return {
restrict: 'EA',
transclude: true,
scope: {
testFunc : '&'
},
link: function(scope) {
node.on("click", click);
function click(d) {
scope.$apply(function () {
scope.testFunc();
});
}
};
}]);

Answer 1

You shouldn't really be using controllers and directives. Angularjs is meant to be used as more of a component(directive) based structure and controllers are more page centric. However if you are going to be doing it this way, there are two ways you can go about it.
First Accessing $parent:
If your directive is inside the controllers scope you can access it using scope.$parent.mainController.testFunc();
Second (Preferred Way):
Create a service factory and store your function in there.
d3DemoApp.factory('clickFactory', [..., function(...) {
var service = {}
service.testFunc = function(...) {
//do something
}
return service;
}]);
d3DemoApp.directive('directiveName', ['clickFactory', function(clickFactory) {
return {
restrict: 'EA',
transclude: true,
link: function(scope, elem) {
elem.on("click", click);
function click(d) {
scope.$apply(function () {
clickFactory.testFunc();
});
}
};
}]);
Just a tip, any time you are using a directive you don't need to add $scope to the top of it. scope and scope.$parent is all you really need, you will always have the scope context. Also if you declare scope :{} in your directive you isolate the scope from the rest of the scope, which is fine but if your just starting out could make things quite a bit more difficult for you.

Answer 2

In your link function you are using node, which doesn't exist. Instead you must use element which is the second parameter to link.
link: function(scope, element) {
element.on("click", click);
function click(d) {
scope.$apply(function() {
scope.testFunc();
});
}