How does Objective-C's asynchronous request model work?
I've been playing with Objective-C the past couple of weeks and have a working app that performs an async HTTP Request to pull some data from Twitter. 

I come from a web application background and have become use to how Javascript handles callbacks by passing a function that is called when a XHR request is done loading. As such, I find Objective-C's model of handling async requests with delegate objects and the perfomSelector method pretty darn cool.

    [callbackObj performSelector:@selector(callbackMethod:) withObject:argObj];

So my question is, what is the design of Objective-C's async model and how does it work?


How does Objective-C's asynchronous request model work?
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I've been playing with Objective-C the past couple of weeks and have a working app that performs an async HTTP Request to pull some data from Twitter. 

I come from a web application background and have become use to how Javascript handles callbacks by passing a function that is called when a XHR request is done loading. As such, I find Objective-C's model of handling async requests with delegate objects and the perfomSelector method pretty darn cool.

    [callbackObj performSelector:@selector(callbackMethod:) withObject:argObj];

So my question is, what is the design of Objective-C's async model and how does it work?

