CBCentralManagerDelegate protocol defines the methods that a delegate of a
CBCentralManager object must adopt. The optional methods of the protocol allow the delegate to monitor the discovery, connectivity, and retrieval of peripheral devices. The only required method of the protocol indicates the availability of the central manager, and is called when the central manager’s state is updated.
- iOS 5.0+
- macOS 10.7+
- tvOS 9.0+