GyroViewModel2.swift

import CoreMotion

class GyroViewModel: CMMotionManager, ObservableObject {
  var timer = Timer()
  
  @Published var x: Double = 0
  @Published var y: Double = 0
  @Published var z: Double = 0
  
  func start() {
      if isDeviceMotionAvailable {
          deviceMotionUpdateInterval = 1.0 / 60.0
          showsDeviceMovementDisplay = true
          startDeviceMotionUpdates(using: .xMagneticNorthZVertical)
        
          self.timer = Timer(fire: Date(),
                             interval: (1.0 / 60.0),
                             repeats: true) { (timer) in
              self.x = self.deviceMotion?.attitude.pitch ?? 0
              self.y = self.deviceMotion?.attitude.roll ?? 0
              self.z = self.deviceMotion?.attitude.yaw ?? 0
          }
          RunLoop.current.add(self.timer, forMode: RunLoop.Mode.default)
      }
  }
  
  func stop() {
    timer.invalidate()
    stopDeviceMotionUpdates()
  }
}