Dart representation of CXHandle from iOS CallKit Framework
A means by which a call recipient can be reached, such as a phone number or email address.
When the telephony provider receives an incoming call or the user starts an outgoing call, the other caller is identified by a CXHandle object.
For a caller identified by a phone number, the handle type is FCXHandleType.PhoneNumber and the value is a sequence of digits.
For a caller identified by an email address, the handle type is FCXHandleType.EmailAddress and the value is an email address.
For a caller identified in any other way, the handle type is FCXHandleType.Generic and the value typically follows some domain-specific format, such as a username, numeric ID, or URL.