Tutorial by Examples

From Apple documentation: Use the CTCallCenter class to obtain a list of current cellular calls, and to respond to state changes for calls such as from a dialing state to a connected state. Such state changes are known as cellular call events. The purpose of CTCallCenter is to give the develop...

//Header File <CallKit/CXCallObserver.h> CXCallObserver *callObserver = [[CXCallObserver alloc] init]; // If queue is nil, then callbacks will be performed on main queue [callObserver setDelegate:self queue:nil]; // Don't forget to store reference to callObserver, to prevent it ...