Swiz and MockAsyncToken
I've been taking a look at the applicability of Chris Scott's Swiz Framework for use here at Broadchoice. So far, it's exactly what I'd expect - a fairly noninvasive way of wiring dependencies inside a Flex / AIR application that allows use of inversion-of-control.
One thing that threw me, though, was that Swiz approaches business delegates (wrappers for business services like RemoteObjects) from a total RPC standpoint. Instead of passing an IResponder to a new delegate instance each time you wish to use it like most Flex frameworks encourage, you simply write a delegate, instantiate it once in your BeanLoader, and use it as a singleton. Each of its methods that make server-side calls just return AsyncToken instances.
I really like this, as it makes the difference between a simple RemoteObject and a delegate wrapper completely irrelevant - your controller doesn't have a clue if it's talking to a delegate or not.
It did, however, throw me off from something I typically do. I normally write a "mock" delegate for any business service that "pretends" the server is there. Its useful in both unit tests and day to day coding: server may be down, backend code not written, etc.
In order to get this to work with Swiz, however, I had to simulate the presense of an AsyncToken and its related RPC events. Hence, I've cobbled together a MockAsyncToken and MockResultEvent that let you quickly set what you'd like a mock delegate to return:
// Mock'd RPC function
public function getUser() : AsyncToken
{
// just pass the desired server response to the MockAsyncToken's constructor
return new MockAsyncToken(new User());
}
...bam. Instant mock delegate. Thanks to Swiz, the rest of the app doesn't care that it's even there, and if I can use a plain RemoteObject, I never even have to write the "real" delegate.
Code for MockAsyncToken and MockResultEvent (dependency) is attached. Use at your own peril.
This is exactly what I was looking for, thx!