ios - 从 CMPedometer 检索数据时出现问题 : "Error on message reply (Connection invalid)"

Question

我尝试使用 CoreMotion 的 CMPedometer 获取步数，但我在日志中收到以下错误，而不是步数:消息回复错误(连接无效)。下面的示例在设备(而不是模拟器)上运行。

代码(ViewController.swift中的viewDidLoad内部):

let pedometer = CMPedometer()
if CMPedometer.isStepCountingAvailable() {
    print("Step counting is available...")
    let calendar = Calendar.current
    let fromDate = calendar.startOfDay(for: Date())
    let toDate = Date()
    print("From date = \(fromDate)")
    print("To date = \(toDate)")
    pedometer.queryPedometerData(from: fromDate, to: toDate) { (data, error) in
    print("Handler (data):")
    print(data!)
}

日志:

Step counting is available...
From date = 2019-06-15 22:00:00 +0000
To date = 2019-06-15 22:48:35 +0000
2019-06-16 00:48:40.827268+0200 StepTest2[3857:1087379] [Generic_deprecated] Error on message reply (Connection invalid)

Answer 1

似乎 let pedometer = CMPedometer() 必须是非本地的，例如在 viewDidLoad 外部的类中声明。几乎所有代码:

@IBOutlet weak var stepLabel: UILabel!
let pedometer = CMPedometer()
override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.

    if CMPedometer.isStepCountingAvailable() {
        print("Step counting is available...")
        let calendar = Calendar.current
        var toDate = Date()
        var fromDate = calendar.startOfDay(for: toDate)
        fromDate = calendar.date(byAdding: .hour, value: -24, to: fromDate)!
        toDate = calendar.date(byAdding: .hour, value: 2, to: toDate)!
        print("From date = \(fromDate)")
        print("To date = \(toDate)")

        pedometer.queryPedometerData(from: fromDate, to: toDate) { (data, error) in
            print("Handler (data):")
            print(data!)
            guard let activityData = data, error == nil else {
                print("There was an error getting the data: \(error!)")
                return
            }
            DispatchQueue.main.async {
                self.stepLabel.text = "Steps and distance: \(activityData.numberOfSteps) \(activityData.distance ?? -1)"
            }
        }
    }
}