Translated by OOPer in cooperation with shlab.jp, on 2015/3/29. (Compatibility wrapper created by OOPer in cooperation with shlab.jp, on 2015/9/20.)
Based on https://developer.apple.com/library/ios/samplecode/ABUIGroups/Introduction/Intro.html#//apple_ref/doc/uid/DTS40011307 2013-07-29.
As this is a line-by-line translation from the original sample code, "redistribute the Apple Software in its entirety and without modifications" would apply. See license terms in each file. Some faults caused by my translation may exist. Not all features tested. You should not contact to Apple or SHLab(jp) about any faults caused by my translation.
I added a thin (but not so compact) wrapper intended to work in iOS 7 through 9.
The implementation is rather experimental than practical, and intended to work only with this sample code.
If you need a stable sample code in Swift, retrieve any of the former version.
=========================================================================== BUILD REQUIREMENTS:
Xcode 8.3.3, iOS 10 SDK
=========================================================================== RUNTIME REQUIREMENTS:
iOS 8 or later
===========================================================================