Why is .then not a function?

that service needs to return a promise, not returning the items

populateData: function(data) { var deferred = $q.defer(); var items = []; for (i = 0; i < data.length; i++) { items.push(data[i]); } deferred.resolve(items); return deferred.promise; } 

you might not need this though since you could do

var items = EventService.populateData(result); //Do something with items here 

usually promises are used if you're doing something asynchronously. Like calling an API and waiting for a response. In those cases, the response might take seconds to finish THEN the .then function gets called. in your case if you make that function a promise it will be called almost immediately

EDIT: Here's the link to $q Documentation AngularJS: API: $q

Return something that has a promise or just change your calling code:

populateData: return $http.get("www"); 

or

EventService.getDataFromApi().then(function () { EventService.getDataFromDB().then(function (result) { var response = EventService.populateData(result); $scope.items = response; }); });