We can start writing the app right away. We can split it into three separate parts:
Fetch JSONP data via Reddit API
Render latest articles into a list
Let the user save articles into IndexedDB
It's fair to say that this example doesn't use any special HTML5 features apart from IndexedDB. What's interesting here is how it combines multiple things that we've seen in previous chapters, most importantly, the integration of JavaScript within Dart, its Future-Based API, and JsObject proxy objects. You can use exactly the same approach for any JavaScript that needs to call Dart callbacks.
Simply said, JSONP is a JavaScript object wrapped into a function call and included just like any other JavaScript file (http://en.wikipedia.org/wiki/JSONP). Our app is entirely client side. This means that we can't call Ajax requests to servers on a different domain to ours, and unless the remote server returns appropriate Access-Control-Allow-Origin (ACAO...