motion manager not working

Question

I'am trying to get the device motion (pitch,roll,yaw) but my function handleDeviceMotionUpdate isn't launched (I'am trying it on an iphone 5s) , here is the code :

import UIKit
import CoreMotion

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()






    var motionManager = CMMotionManager()
    motionManager.startDeviceMotionUpdates()
    motionManager.deviceMotionUpdateInterval = 0.1


    motionManager.startDeviceMotionUpdatesToQueue(
        NSOperationQueue.currentQueue()!, withHandler: {
            (deviceMotion, error) -> Void in

            if(error == nil) {
                self.DeviceMotionUpdate(deviceMotion!)
            } else {
                print("error")
            }
    })

}


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()

}

func DeviceMotionUpdate(deviceMotion:CMDeviceMotion) {
    print("function launched")
    var attitude = deviceMotion.attitude
    var roll = (attitude.roll)
    var pitch = (attitude.pitch)
    var yaw = (attitude.yaw)
    print("Roll: \(roll), Pitch: \(pitch), Yaw:  (yaw)")

}



}

I don't get the error in startDeviceMotionUpdatesToQueue . I get true on motionManager.deviceMotionActive and on motionManager.deviceMotionAvailable

Answer 1

Your motionManager probably gets destroyed after it finished running the viewDidLoad method. Try making motionManager a class property.

class ViewController: UIViewController {
    var motionManager = CMMotionManager()

    override func viewDidLoad() {
        super.viewDidLoad()

        self.motionManager.startDeviceMotionUpdates()

        ...