Starts recording the app display.
- iOS 10.0+
- tvOS 10.0+
A block that is called when the request completes.
If an error occurred, this parameter holds an object that explains the error. Otherwise, the value of this parameter is
nil. See Errors for a list of error codes specific to ReplayKit.
start on an instance of the recorder to begin recording. When
start is first called, an alert window appears asking the user to confirm recording. This alert window is also presented if it has been longer than 8 minutes since the last time
start was called.