Promise callback not called in Angular JS
angularjs, jquery-deferred, websocket
Solution
In AngularJS promise results are propagated asynchronously, inside a $digest cycle. So, your callback function registered with then() will only be called upon entering a $digest cycle.
So, when your socket connects, we are in a digest cycle. `then()` creates a new promise, but the results of that `then()` will not be propagated until the next digest cycle, which never comes (because there is no `$timeout`, or `$http`, or DOM event to trigger one). As @Ajay just posted, if you add $scope.$apply(), it will cause a digest cycle and you'll see the results.
Problem
If I call `connect` from `doStuff`, I get the message that "the socket is connected", but the `callback` is not called. What am I missing here? ``` $scope.connect = function() { var defer = $q.defer(); ws = new WebSocket("ws://server.com:port"); ws.onopen = function(){ console.log("Socket connected"); defer.resolve("socket connected"); }; return defer.promise; } $scope.doStuff = function() { $scope.connect().then(function(data) { console.log("And we're off!", data); }); } ```