A NSOperation subclass that makes chaining time-consuming async operations a breeze
While it's easy to perform async operations with GCD, for more complex operations involving blocks of connected work, where the results of one producer operation (eg. a download) need to be used at some point by a consumer operation (eg. data processing followed by overwriting to a remote server)...yeah, that stuff is more challenging. This demo app includes code you can follow to see how to use NSOperation subclasses with NSBlockOperations to pass data along an NSOperationQueue...and it also gives a handy-dandy custom class -- MPC_NSOperation - and a NSOperationQueue custom category to make the whole process easier. There are even a bunch of re-usable CloudKit subclasses in there as a bonus.