[ios] some issue: async, guid, priority queue, view fade-in, image reflection

How do I wait for an asynchronously dispatched block to finish?

http://stackoverflow.com/questions/4326350/how-do-i-wait-for-an-asynchronously-dispatched-block-to-finish

Waiting on asynchronous methods using NSCondition

http://stackoverflow.com/questions/14013947/waiting-on-asynchronous-methods-using-nscondition

How to create a GUID/UUID using the iPhone SDK

http://stackoverflow.com/questions/427180/how-to-create-a-guid-uuid-using-the-iphone-sdk

jessedc / JCPriorityQueue

https://github.com/jessedc/JCPriorityQueue/tree/experimental/heap-queue

Fade/dissolve when changing UIImageView's image

http://stackoverflow.com/questions/7638831/fade-dissolve-when-changing-uiimageviews-image

No-fuss reflections – generating reflections the easy way in iOS

http://aptogo.co.uk/2011/08/no-fuss-reflections/