gistfile1.txt

        if CMPedometer.isStepCountingAvailable() {
            self.pedometer.startUpdates(from: NSDate() as Date) {
                (data: CMPedometerData?, error) -> Void in
                // アクティビティが変化するたびに呼ばれる
                DispatchQueue.main.async(execute: { () -> Void in
                    if (error == nil) {
                        let steps = data!.numberOfSteps
                        self.stepLabel.text = "steps: \(steps)"
                    }
                })
            }
        }