CMMotionManager和CMMotionActivityManager在Swift中显示错误的值

Question

我正在尝试使用CMMotionManager来跟踪用户是跑步，走路还是开车。静止时，显示驾驶，表明它显示旧值。我该如何清除缓存，以便显示正确的内容，或者我的代码是否有问题，导致手机在静止时显示为自动：

这是我的代码：

//at beginning of class

 let motionManager = CMMotionManager()
 let motionActivityManager = CMMotionActivityManager()

 //in viewdidload

 if self.motionManager.isAccelerometerAvailable {
             self.motionManager.accelerometerUpdateInterval = 0.01
            motionActivityManager.startActivityUpdates(to: .main) { (activity) in
                guard let activity = activity else {             
                    return
                }
                if activity.walking {
                      self.rightBarButton.title = "‍"
                }
                else if activity.running {
                         self.rightBarButton.title = "‍"
                }
                else if activity.cycling {
                         self.rightBarButton.title = "‍"
                }
                else if activity.automotive {
                         self.rightBarButton.title = ""  
                }
                else { 
                 self.rightBarButton.title = "not moving"
                }
            }
        }