In AngularJS, how to detect when user leaves template/page?

Question

I am using the Javascript command: setInterval. I like to stop it when the user leaves the page.

This code seems to work well: http://jsfiddle.net/PQz5k/

It detects when a user leaves a page. It executes Javascript code when a user clicks on a link to go to a different HTML page or URL, or if user reloads page.

However, it does not work when I go from one AngularJS template to another. As an example, if I am at template1.html, I want the Javascript code to do something in Controller1.js when the user leaves template1.html to go to template2.html. What is the equivalent of this code below in AngularJS?:

$(window).on('beforeunload', function() {
    return 'Your own message goes here...';
});

Are you actually switching full pages at the html root or are you switching templates in an ng-view? — Brad Green, Dec 17 '12 at 05:14

Mathew Berg · Accepted Answer · 2017-04-03T14:55:04.980

143

I think you have two controllers, one for each template like this:

function Controller_1($scope...){
    ...
}
function Controller_2($scope...){
    ...
}

Well, when you switch from one template to another there's an event that's fired called $destroy, you can read up on it here http://docs.angularjs.org/api/ng.$rootScope.Scope#$destroy

Let's say I'm switching from the template with Controller_1 to the template with Controller_2. Controller_1 has an interval I'd like to stop. You can accomplish this with:

function Controller_1($scope, $interval...){
    var myInterval = $interval(...);
    $scope.$on("$destroy", function(){
        $interval.cancel(myInterval);
    });
}

This will mean that when the $scope for Controller_1 is destroyed, the event will be called and the interval will be cleared.

edited Apr 03 '17 at 14:55

answered Dec 17 '12 at 15:51

Mathew Berg

28,625
11
69
90

1

@Matthew Berg: Thanks for your help! That worked. However, I now have another problem. I have multiple functions in my Controller1, which are executed by different buttons/links on Template1. When I click on those links, the SetInterval is still running. I've even put ClearInterval(myInterval) in the function that calls SetInterval, but it still does not stop the SetInterval. – Curt Dec 20 '12 at 02:51
I think I found the other part of the solution at http://stackoverflow.com/questions/8476045/how-to-stop-setinterval I have to clear the myInterval variable at the top of the Controller so that it is exposed to all of my functions. – Curt Dec 20 '12 at 03:44
8

`$scope.$on('$destroy')` works but you should use `$interval.cancel(myInterval);` to keep with the angular way. – chovy Nov 28 '13 at 07:53
You have to destroy the interval when the scope is destroyed, so $interval.cancel will not help you. I.e. you have a view with a controller that continuously needs to run an interval and only when you leave the view do you want the interval to stop. – Mathew Berg Nov 28 '13 at 11:20
Awesome tip! That makes such a nice clean way to handle setInterval ids. Thanks! – tonejac Jul 10 '16 at 21:37

score 12 · Answer 2 · answered Dec 11 '14 at 18:57

This is for when you leave a template (also prompt a confirm dialog):

             function Controller_1($scope...){
               var myInterval = setInterval(...);
               $scope.$on('$locationChangeStart', function (event, next, current) {
                    console.log(current);

                    if (current.match("\/yourCurrentRoute")) {
                        var answer = confirm("Are you sure you want to leave this page?");
                        if (!answer) {
                            event.preventDefault();
                        }else{
                            clearInterval(myInterval);
                        }
                    }
                });
               }

score 7 · Answer 3 · answered Sep 07 '15 at 15:37

if you are using ui-router then you can use the onExit, property

    $stateProvider.state('foo', {
        url: '/foo',        
        templateUrl: 'views/foo.html',    
        controller: 'fooController',
        onExit: ['$fooService', function($fooService) => {
            $fooService.hide();//do what u want to do here
        }]

    });

score 0 · Answer 4 · answered Apr 15 '15 at 18:52

You can use a watcher to check when the location path is changed, something like this:

$scope.$watch(function(){
    return $location.path();
}, function(newPath, oldPath){
   //...Do something
})

Then, you can get the old location, and the new location and execute a function or whatever you want,

In AngularJS, how to detect when user leaves template/page?

4 Answers4

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