Call method in directive controller from other controller

Javascript Jquery Angularjs Angularjs Directive

Javascript Problem Overview

I have a directive that has its own controller. See the below code:

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

popdown.directive('popdown', function () {
    var PopdownController = function ($scope) {
        this.scope = $scope;
    }

    PopdownController.prototype = {
        show:function (message, type) {
            this.scope.message = message;
            this.scope.type = type;
        },

        hide:function () {
            this.scope.message = '';
            this.scope.type = '';
        }
    }

    var linkFn = function (scope, lElement, attrs, controller) {

    };

    return {
        controller: PopdownController,
        link: linkFn,
        replace: true,
        templateUrl: './partials/modules/popdown.html'
    }

});

This is meant to be a notification system for errors/notifications/warnings. What I want to do is from another controller (not a directive one) to call the function show on this controller. And when I do that, I would also want my link function to detect that some properties changed and perform some animations.

Here is some code to exemplify what I'm asking for:

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

app.controller('IndexController', function($scope, RestService) {
    var result = RestService.query();
    
    if(result.error) {
        popdown.notify(error.message, 'error');
    }
});

So when calling show on the popdown directive controller, the link function should also be triggered and perform an animation. How could I achieve that?

Javascript Solutions

Solution 1 - Javascript

This is an interesting question, and I started thinking about how I would implement something like this.

I came up with this (fiddle);

Basically, instead of trying to call a directive from a controller, I created a module to house all the popdown logic:

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

I put two things in the module, a factory for the API which can be injected anywhere, and the directive for defining the behavior of the actual popdown element:

The factory just defines a couple of functions success and error and keeps track of a couple of variables:

PopdownModule.factory('PopdownAPI', function() {
    return {
        status: null,
        message: null,
        success: function(msg) {
            this.status = 'success';
            this.message = msg;
        },
        error: function(msg) {
            this.status = 'error';
            this.message = msg;
        },
        clear: function() {
            this.status = null;
            this.message = null;
        }
    }
});

The directive gets the API injected into its controller, and watches the api for changes (I'm using bootstrap css for convenience):

PopdownModule.directive('popdown', function() {
    return {
        restrict: 'E',
        scope: {},
        replace: true,
        controller: function($scope, PopdownAPI) {
            $scope.show = false;
            $scope.api = PopdownAPI;
            
            $scope.$watch('api.status', toggledisplay)
            $scope.$watch('api.message', toggledisplay)
            
            $scope.hide = function() {
                $scope.show = false;
                $scope.api.clear();
            };
            
            function toggledisplay() {
                $scope.show = !!($scope.api.status && $scope.api.message);               
            }
        },
        template: '<div class="alert alert-{{api.status}}" ng-show="show">' +
                  '  <button type="button" class="close" ng-click="hide()">&times;</button>' +
                  '  {{api.message}}' +
                  '</div>'
    }
})

Then I define an app module that depends on Popdown:

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

app.controller('main', function($scope, PopdownAPI) {
    $scope.success = function(msg) { PopdownAPI.success(msg); }
    $scope.error   = function(msg) { PopdownAPI.error(msg); }
});

And the HTML looks like:

<html ng-app="app">
    <body ng-controller="main">
        <popdown></popdown>
        <a class="btn" ng-click="success('I am a success!')">Succeed</a>
        <a class="btn" ng-click="error('Alas, I am a failure!')">Fail</a>
    </body>
</html>

I'm not sure if it's completely ideal, but it seemed like a reasonable way to set up communication with a global-ish popdown directive.

Again, for reference, the fiddle.

Solution 2 - Javascript

You can also use events to trigger the Popdown.

Here's a fiddle based on satchmorun's solution. It dispenses with the PopdownAPI, and the top-level controller instead $broadcasts 'success' and 'error' events down the scope chain:

$scope.success = function(msg) { $scope.$broadcast('success', msg); };
$scope.error   = function(msg) { $scope.$broadcast('error', msg); };

The Popdown module then registers handler functions for these events, e.g:

$scope.$on('success', function(event, msg) {
    $scope.status = 'success';
    $scope.message = msg;
    $scope.toggleDisplay();
});

This works, at least, and seems to me to be a nicely decoupled solution. I'll let others chime in if this is considered poor practice for some reason.

Solution 3 - Javascript

You could also expose the directive's controller to the parent scope, like ngForm with name attribute does: http://docs.angularjs.org/api/ng.directive:ngForm

Here you could find a very basic example how it could be achieved http://plnkr.co/edit/Ps8OXrfpnePFvvdFgYJf?p=preview

In this example I have myDirective with dedicated controller with $clear method (sort of very simple public API for the directive). I can publish this controller to the parent scope and use call this method outside the directive.

Solution 4 - Javascript

I got much better solution .

here is my directive , I have injected on object reference in directive and has extend that by adding invoke function in directive code .

app.directive('myDirective', function () {
    return {
        restrict: 'E',
        scope: {
        /*The object that passed from the cntroller*/
        objectToInject: '=',
        },
        templateUrl: 'templates/myTemplate.html',

        link: function ($scope, element, attrs) {
            /*This method will be called whet the 'objectToInject' value is changes*/
            $scope.$watch('objectToInject', function (value) {
                /*Checking if the given value is not undefined*/
                if(value){
                $scope.Obj = value;
                    /*Injecting the Method*/
                    $scope.Obj.invoke = function(){
                        //Do something
                    }
                }    
            });
        }
    };
});

Declaring the directive in the HTML with a parameter:

<my-directive object-to-inject="injectedObject"></ my-directive>

my Controller:

app.controller("myController", ['$scope', function ($scope) {
   // object must be empty initialize,so it can be appended
    $scope.injectedObject = {};

    // now i can directly calling invoke function from here 
     $scope.injectedObject.invoke();
}];

Content Type	Original Author	Original Content on Stackoverflow
Question	user253530	View Question on Stackoverflow
Solution 1 - Javascript	satchmorun	View Answer on Stackoverflow
Solution 2 - Javascript	Aron	View Answer on Stackoverflow
Solution 3 - Javascript	luacassus	View Answer on Stackoverflow
Solution 4 - Javascript	Ashwini Jindal	View Answer on Stackoverflow