ios - 如何在 Xcode 的 map 中显示我当前的位置？

Question

我在 YouTube 上观看了一些类(class)，现在尝试获得实践经验。我正在进行一个小项目，其中涉及一个选项卡式应用程序，我尝试在第一页上创建一个带有显示当前位置的按钮的 map 。实际上很基本。但不知怎的，它就是不起作用，我不知道问题是什么。 CodewithChris 的某人告诉我:“我建议将您的应用程序分解为更小的组件，并确保每个组件都能正常工作，然后再继续下一个组件。尝试先输出您的位置，然后再将其绘制在 map 等上，这样您就可以更轻松地定位错误。”我只是不明白她所说的更小的组件是什么意思。我真的很感谢我能得到的所有帮助。下面是尽可能好的代码。预先感谢您的帮助。

import UIKit

import MapKit

import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {

    @IBOutlet var textFieldForAddress: UITextField!
    @IBOutlet var getDirectionsButton: UIButton!
    @IBOutlet var map: MKMapView!

    var locationManger = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()

        locationManger.delegate = self
        locationManger.desiredAccuracy = kCLLocationAccuracyBest
        locationManger.requestAlwaysAuthorization()
        locationManger.requestWhenInUseAuthorization()
        locationManger.startUpdatingLocation()

        map.delegate = self

    }

    @IBAction func getDirectionsTapped(_ sender: Any) {
        getAddress()
    }


    func getAddress() {
        let geoCoder = CLGeocoder()
        geoCoder.geocodeAddressString(textFieldForAddress.text!) { (placemarks, error) in
            guard let placemarks = placemarks, let location = placemarks.first?.location
                else {
                    print("No Location Found")
                    return
            }
            print(location)
            self.mapThis(destinationCord: location.coordinate)

        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        print(locations)
    }

    func mapThis(destinationCord : CLLocationCoordinate2D) {

        let souceCordinate = (locationManger.location?.coordinate)!

        let soucePlaceMark = MKPlacemark(coordinate: souceCordinate)
        let destPlaceMark = MKPlacemark(coordinate: destinationCord)

        let sourceItem = MKMapItem(placemark: soucePlaceMark)
        let destItem = MKMapItem(placemark: destPlaceMark)

        let destinationRequest = MKDirections.Request()
        destinationRequest.source = sourceItem
        destinationRequest.destination = destItem
        destinationRequest.transportType = .automobile
        destinationRequest.requestsAlternateRoutes = true

        let directions = MKDirections(request: destinationRequest)
        directions.calculate { (response, error) in
            guard let response = response else {
                if let error = error {
                    print("Something is wrong :(")
                }
                return
            }

          let route = response.routes[0]
          self.map.addOverlay(route.polyline)
          self.map.setVisibleMapRect(route.polyline.boundingMapRect, animated: true)

        }


    }

    func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
        let render = MKPolylineRenderer(overlay: overlay as! MKPolyline)
        render.strokeColor = .blue
        return render
    }


}

Answer 1

如果要显示用户位置并让 map 跟踪它，则需要在 map View 上设置两个属性 - showsUserLocation 和 userTrackingMode。为了使 map 能够访问用户位置，您必须使用 CLocationManager 从用户那里接收 whenInUse 授权。

import MapKit

import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {

    @IBOutlet var textFieldForAddress: UITextField!
    @IBOutlet var getDirectionsButton: UIButton!
    @IBOutlet var map: MKMapView!

    var locationManger = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()

        locationManger.requestWhenInUseAuthorization()
        map.showsUserLocation = true
        map.userTrackingMode = .follow

    }

如果您在模拟器上运行，则需要使用模拟器中的调试菜单来模拟位置。