138
votes

Stack trace:

Error: $apply already in progress
at Error (<anonymous>)
at beginPhase (file:///android_asset/www/built.min.js:7:22740)
at Object.Scope.$apply (file:///android_asset/www/built.min.js:7:25967)
at navigator.geolocation.getCurrentPosition.that (file:///android_asset/www/built.min.js:13:8670)
at Object.geolocation.getCurrentPosition (file:///android_asset/www/plugins/org.apache.cordova.core.geolocation/www/geolocation.js:122:13)
at Object.getCurrentPosition (file:///android_asset/www/built.min.js:13:8589)
at Object.getCurrentPosition (file:///android_asset/www/built.min.js:13:8277)
at Object.getCurrentCity (file:///android_asset/www/built.min.js:13:8941)
at Object.$scope.locateDevice (file:///android_asset/www/built.min.js:13:10480)
at file:///android_asset/www/built.min.js:7:12292:7

refers to this code http://pastebin.com/B9V6yvFu

    getCurrentPosition: cordovaReady(function (onSuccess, onError, options) {

        navigator.geolocation.getCurrentPosition(function () {
            var that = this,
                args = arguments;

            if (onSuccess) {
                $rootScope.$apply(function () {
                    onSuccess.apply(that, args);
                });
            }
        }, function () {
            var that = this,
                args = arguments;
            if (onError) {
                $rootScope.$apply(function () {
                    onError.apply(that, args);
                });
            }
        }, {
            enableHighAccuracy: true,
            timeout: 20000,
            maximumAge: 18000000
        });
    })

Strange thing, on my LG4X it works fine, however on my samsung s2 it throws the above error. Any ideas whats wrong?

12
Have you tried stackoverflow.com/a/12859093/1266600? It might be because different devices -> different processing speeds -> different timings, which may cause conflicts in some places but not others. - sushain97
use $timeout() - Onur Yıldırım
+1 to the $timeout() comment. See: stackoverflow.com/questions/12729122/… - Trevor

12 Answers

108
votes

You are getting this error because you are calling $apply inside an existing digestion cycle.

The big question is: why are you calling $apply? You shouldn't ever need to call $apply unless you are interfacing from a non-Angular event. The existence of $apply usually means I am doing something wrong (unless, again, the $apply happens from a non-Angular event).

If $apply really is appropriate here, consider using a "safe apply" approach:

https://coderwall.com/p/ngisma

56
votes

Just use $evalAsync instead of $apply.

42
votes

You can use this statement:

if ($scope.$root.$$phase != '$apply' && $scope.$root.$$phase != '$digest') {
    $scope.$apply();
}
24
votes

If scope must be applied in some cases, then you can set a timeout so that the $apply is deferred until the next tick

setTimeout(function(){ scope.$apply(); });

or wrap your code in a $timeout(function(){ .. }); because it will automatically $apply the scope at the end of execution. If you need your function to behave synchronously, I'd do the first.

10
votes

In my case i use $apply with angular calendar UI to link some event:

$scope.eventClick = function(event){           
    $scope.$apply( function() {
        $location.path('/event/' + event.id);
    });
};

After reading the doc of the problem: https://docs.angularjs.org/error/$rootScope/inprog

The part Inconsistent API (Sync/Async) is very interesting:

For example, imagine a 3rd party library that has a method which will retrieve data for us. Since it may be making an asynchronous call to a server, it accepts a callback function, which will be called when the data arrives.

Since, the MyController constructor is always instantiated from within an $apply call, our handler is trying to enter a new $apply block from within one.

I change the code to :

$scope.eventClick = function(event){           
    $timeout(function() {
        $location.path('/event/' + event.id);
    }, 0);
};

Works like a charm !

Here we have used $timeout to schedule the changes to the scope in a future call stack. By providing a timeout period of 0ms, this will occur as soon as possible and $timeout will ensure that the code will be called in a single $apply block.

9
votes

In angular 1.3, I think, they added a new function - $scope.$applyAsync(). This function calls apply later on - they say about 10 ms later at least. It is not perfect, but it does at least eliminate the annoying error.

https://docs.angularjs.org/api/ng/type/$rootScope.Scope#$applyAsync

3
votes

At any point in time, there can be only one $digest or $apply operation in progress. This is to prevent very hard to detect bugs from entering your application. The stack trace of this error allows you to trace the origin of the currently executing $apply or $digest call, which caused the error.

More info: https://docs.angularjs.org/error/$rootScope/inprog?p0=$apply

2
votes

Just resolved this issue. Its documented here.

I was calling $rootScope.$apply twice in the same flow. All I did is wrapped the content of the service function with a setTimeout(func, 1).

2
votes

I know it's old question but if you really need use $scope.$applyAsync();

0
votes

I call $scope.$apply like this to ignored call multiple in one times.

      var callApplyTimeout = null;
      function callApply(callback) {
          if (!callback) callback = function () { };
          if (callApplyTimeout) $timeout.cancel(callApplyTimeout);

          callApplyTimeout = $timeout(function () {
              callback();
              $scope.$apply();
              var d = new Date();
              var m = d.getMilliseconds();
              console.log('$scope.$apply(); call ' + d.toString() + ' ' + m);
          }, 300);
      }

simply call

callApply();
0
votes

We can use setTimeout function in such cases.

console.log('primary task');

setTimeout(function() {
  
  console.log('secondary task');

}, 0);

This will make sure that secondary task will be executed when execution of primary task is finished.

0
votes

You can $apply your changes only if $apply is not already in progress. You can update your code as

if(!$scope.$$phase) $scope.$apply();