Its odd that it's not a standard iOS feature to cancel a UIActionSheet by tapping outside/above it, and it's actually a bit tricky to code it. But here it is:
Thanks for reading! And if you want to get in touch, I'd love to hear from you: chris.hulbert at gmail.
(Comp Sci, Hons - UTS)
iOS Developer (Freelancer / Contractor) in Australia.
I have worked at places such as Google, Cochlear, Assembly Payments, News Corp, Fox Sports, NineMSN, FetchTV, Woolworths, and Westpac, among others. If you're looking for help developing an iOS app, drop me a line!