CXCallController
A programmatic interface for interacting with and observing calls.
Declaration
class CXCallControllerOverview
A CXCallController object interacts with calls by performing actions, which are represented by instances of CXCallAction subclasses. You can request that one or more actions be performed in a single CXTransaction object using the request(_:completion:) method. A transaction may be rejected by the system for one of the reasons listed in the CXErrorCodeRequestTransactionError.Code enumeration.
Each CXCallController object manages a CXCallObserver object, which can be accessed using the callObserver property. You can provide an object conforming to the CXCallObserverDelegate protocol to the call observer in order to be notified of any changes to active calls.