AngularJS Update Scope $q

Question

So recently I've been updating something that looks like the below:

$scope.arrayOfThings = [];

function setArrayOfThings() {
     thingsService.get().then(function (things) {
         $scope.arrayOfThings = things;
     });
}

$scope.$on('arrayOfThings.add', setArrayOfThings);

To look more like this (using the lesser-known promise integration into bindings...):

$scope.arrayOfThings = thingsService.get();

But how do I force arrayOfThings to update (or re-resolve?) when the collection is changed from another $scope?

Is there a better way of doing it than this? http://stackoverflow.com/questions/12576798/angularjs-how-to-watch-service-variables — Jamie, Sep 01 '13 at 18:35
I went with the `registerObserver` pattern (for now). http://stackoverflow.com/a/18569315/491468 — Jamie, Sep 03 '13 at 07:55

score 0 · Answer 1 · answered Aug 30 '13 at 13:10

arrayOfThings can be seen only inside a child scope, so any change of arrayOfThings in a child scope will maintain data-binding anyway. The data-binding has to be resolve manually by $scope.$apply if the arrayOfThing is changed from an event (DOM event, $broadcast, etc)

score 0 · Answer 2 · answered Aug 30 '13 at 14:02

0

You need to put a watch on the service call thingsService.get in the controller that you want to be notified of a change. Like this:

$scope.$watch(thingsService.get, function(newVal, oldVal){
  $scope.arrayOfThings2 = newVal;  
} );

This is assuming you are injecting that service into the new controller.

answered Aug 30 '13 at 14:02

BoxerBucks

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Causes a digest exception - also this wouldn't work for methods with parameters? – Jamie Sep 01 '13 at 18:11
Hmm. There must be something else going on. I have used this a lot to react to data changes in services. Sure, you can pass parameters into the service call if you want. – BoxerBucks Sep 02 '13 at 18:40

AngularJS Update Scope $q

2 Answers2