在Mapbox标签上显示实时信息

Question

我正在尝试在Mapbox的标签上显示实时倒计时数据。当前，用户需要通过以下方式“刷新”地图：在标签外单击，然后再次单击标签或终止应用程序以显示更新的倒计时信息。标签升起时有没有办法显示实时倒计时？

import Mapbox

class ViewController: UIViewController, MGLMapViewDelegate {
    var countdownTimer: Timer!
    var totalTime = 5000
    let test = MGLPointAnnotation()

    override func viewDidLoad() {
        super.viewDidLoad()
        startTimer()
        check()
    }

    func startTimer() {
        countdownTimer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(updateTime), userInfo: nil, repeats: true)
    }

    @objc func updateTime() {

        let(h,m,s) = self.secondsToHoursMinutesSeconds(seconds: self.totalTime)
        var hours = h
        var min = m
        var seconds = s
                 test.subtitle = "time Remaining: \(hours) hours　\(min)minutes　\(seconds)seconds "
        if totalTime != 0 {
            totalTime -= 1
        } else {
            endTimer()
        }
    }

    func endTimer() {
        countdownTimer.invalidate()
    }

    func check(){

    let mapView = MGLMapView(frame: view.bounds)
    mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]

    view.addSubview(mapView)

    mapView.delegate = self

    mapView.showsUserLocation = true
    mapView.setUserTrackingMode(.follow, animated: true)

    self.test.coordinate = CLLocationCoordinate2D(latitude: -157.222, longitude: 24.444)
    self.test.title = "test"
    mapView.addAnnotation(self.test)
    }

    func secondsToHoursMinutesSeconds (seconds : Int) -> (Int, Int, Int) {
        return (seconds / 3600, (seconds % 3600) / 60, (seconds % 3600) % 60)
    }

    func mapView(_ mapView: MGLMapView, viewFor annotation: MGLAnnotation) -> MGLAnnotationView? {
        return nil
    }

    func mapView(_ mapView: MGLMapView, annotationCanShowCallout annotation: MGLAnnotation) -> Bool {
        return true
    }
}