根据用户位置绘制折线 [SWIFT]

Question

我创建了一个应用程序，其中我使用 (MapKit) 制作了一张地图，当我按下“开始”时，它会自动放大我的位置并放置注释。

但是从这里开始，我很困惑。我正在尝试从起始位置到当前位置绘制一条折线。 （并更新我所做的每一个动作）。举个例子，如果我向北走 300 米，我应该能够查看手机上的地图并看到折线在跟随我。

所以从注解开始----->（折线）到用户。并随时更新（这样你就可以看到线条在移动

我怎样才能做到这一点？如果您知道，请在 cmets 中告诉我。我会非常感谢它！ :)

在正确位置添加注解的代码：

@IBAction func StartWalk(_ sender: Any)
    {
        if play == true
        {
            play = false

            //Set resetbutton disabled.
            ResetButton.isHidden = true

            //Set new image when play is true
            PlayStop.setImage(UIImage(named: "Stop"), for: .normal)

            //Bool to check if button is stopped (op)
            isStopped = false

            //Checking userpermission to allow map and current location
            if (CLLocationManager.locationServicesEnabled())
            {
                locationManager.requestAlwaysAuthorization()
                locationManager.requestWhenInUseAuthorization()

                //Retrieve current position
                if let userLocation = locationManager.location?.coordinate
                {
                    //Zooming in to current position
                    let viewRegion = MKCoordinateRegion(center: userLocation, latitudinalMeters: 200, longitudinalMeters: 200)
                    mapView.setRegion(viewRegion, animated: false)

                    //Creating a start annotation
                    let annotation = MKPointAnnotation()
                    annotation.title = "Start"
                    annotation.coordinate = userLocation
                    mapView.addAnnotation(annotation)


                }
            }

        }

    }

这是折线的想法：

//Create polyline
    func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer
    {
        if(overlay is MKPolyline)
        {
            let polyLineRender = MKPolylineRenderer(overlay: overlay)
            polyLineRender.strokeColor = UIColor.blue.withAlphaComponent(1)
            polyLineRender.lineWidth = 3

            return polyLineRender
        }

        return MKPolylineRenderer()
    }

    //Updating location + polylines
    @objc func update()
    {
        //Startposition
        let startLat = locationManager.location?.coordinate.latitude
        let startlong = locationManager.location?.coordinate.longitude
        let startResult = CLLocation(latitude: startLat!, longitude: startlong!)


        //This should be the current user location.
        let stopLat = locationManager.location?.coordinate.latitude
        let stopLong  = locationManager.location?.coordinate.longitude
        let stopResult = CLLocation(latitude: stopLat!, longitude: stopLong!)


        let locations =
        [
            CLLocationCoordinate2D(latitude: startLat!, longitude: startlong!),
            CLLocationCoordinate2D(latitude: stopLat!, longitude: stopLong!)
        ]

            //Draw polyline on the map
            let aPolyLine = MKPolyline(coordinates: locations, count: locations.count)

            //Adding polyline to mapview
            mapView.addOverlay(aPolyLine)

    }

简而言之：

我希望折线从起始位置开始，然后跟随用户走到任何地方，直到按下停止按钮。就像一直在追逐蓝点。你知道吗？请打我

Answer 1

您是否在 ViewController 类上实现方法 MKMapViewDelegate ？

如果您是，您可以从 MapView 访问委托，您必须添加 viewDidLoad 函数或任何其他您希望以下代码和坐标的代码：

mapView.delegate = self
// Connect all the mappoints using Poly line.

 var points: [CLLocationCoordinate2D] = [CLLocationCoordinate2D]()

  for annotation in annotations {
     points.append(annotation.coordinate)
  }     
  var polyline = MKPolyline(coordinates: &points, count: points.count)
  mapView.addOverlay(polyline)

你可以按照下面这个非常好的教程：http://rshankar.com/how-to-add-mapview-annotation-and-draw-polyline-in-swift/

Answer 2

设置为 CLLocationManagerDelegate 和 CoreLocation 将在位置可用时为您提供位置。例如：

import CoreLocation

class MyViewController: UIViewController, CLLocationManagerDelegate {

         override func viewDidLoad() {
            super.viewDidLoad()
            setupCoreLocation()
         }

         func setupCoreLocation() {
            let locationManager = CLLocationManager()
            locationManager.delegate = self

            switch CLLocationManager.authorizationStatus() {
            case .notDetermined:
                locationManager.requestWhenInUseAuthorization()
            case .authorizedWhenInUse:
                // NOTE: I normally only set up "WhenInUse" because "Always"
                // can quickly drain the battery on a device.
                locationManager.startUpdatingLocation()
            default:
                break
            }
        }

        func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
            // Create and add your MKPolyline here based on locations
            // passed (the last element of the array is the most recent
            // position).
        }
}