scope.$on is not working when created inside a directive

Kanagu picture Kanagu · Dec 17, 2013 · Viewed 11.8k times · Source

I have created a directive for my application which is mentioned in the following question How do you serve a file for download with AngularJS or Javascript? Directive code is as like below

    appModule.directive('fileDownload', function ($compile) {
        var fd = {
            restrict: 'A',
            link: function (scope, iElement, iAttrs) {

                scope.$on("downloadFile", function (e, url) {
                    var iFrame = iElement.find("iframe");
                    if (!(iFrame && iFrame.length > 0)) {
                        iFrame = $("<iframe style='position:fixed;display:none;top:-1px;left:-1px;'/>");
                        iElement.append(iFrame);
                    }
                    iFrame.attr("src", url);
                });
            }
        };
        return fd;
    });

Here scope.$on is used, when I call this event via $scope.$emit or $scope.$broadcast, it is not working. My controller code is like below

    function reportsController($scope, $http) {
        var self = this;

        $scope.$broadcast("downloadFile", 'http://google.com');
        $scope.$emit("downloadFile", 'http://google.com');
    }

and my html file is as below

    <div ng-controller="reportsController" id="repctrl">
        <a file-download></a>
    </div>

What I am doing wrong here?

@Edit: Added the subscribe ($on) in the compile phase so as to avoid the usage of $timeout in controller. Here you can look the example

Answer

Austin Greco picture Austin Greco · Dec 17, 2013

I think your controller is being initialized before your directive.. so the $on starts listening after the $emit, $broadcast already happened.

see this plunker

open the console and you can see when the console.logs happen:

controller init happened script.js:16
link happened script.js:7
$scope.test() happened script.js:21
scope.$on happened script.js:9
scope.$on happened 

If you initialize the controller with ng-view or do the emit/broadcast after the directive is created, it should work.