startMagnetometerUpdates(to:withHandler:)
Starts magnetometer updates on an operation queue and with a specified handler.
Declaration
func startMagnetometerUpdates(to queue: OperationQueue, withHandler handler: @escaping CMMagnetometerHandler)Parameters
- queue:
An operation queue provided by the caller. Because the processed events might arrive at a high rate, using the main operation queue is not recommended.
- handler:
A block that is invoked with each update to handle new magnetometer data. The block must conform to the Cmmagnetometerhandler type.
Discussion
You must call stopMagnetometerUpdates() when you no longer want your app to process magnetometer updates.