Learning AngularJS

Using the $q Service to Provide Deferred Responses

An extremely useful service provided by AngularJS is the $q service. The $q service is a promise/deferred response implementation. Since not all services can respond immediately to a request, there is a need to defer the response until the service is ready to respond. That is where the $q service comes in. The idea is that you can make a request, and rather than getting the response directly, you will get a promise that the service will respond. The requesting application can then assign a callback function that should be executed when the deferred request completes successfully or fails.

To utilize the $q service for deferred responses, you will first need to create a deferred object using ...