ios - 如何在 swift 的 map View 上显示位置？我相信我的代码是最新的，但模拟器不显示位置或蓝点？

Question

我正在尝试使用 swift 上的 map View 在 map 上显示我的当前位置和一个蓝点。但是它没有显示我的位置，也没有显示我的代码的蓝点，但我无法显示它!可能是设置的问题？

import UIKit
import MapKit
import CoreLocation

class ViewController: UIViewController {

    @IBOutlet weak var mapView: MKMapView!

    let locationManager = CLLocationManager()
    let regionInMeters: Double = 1000

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


    func setupLocationManager() {
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
    }


    func centerViewOnUserLocation() {
        if let location = locationManager.location?.coordinate {
            let region = MKCoordinateRegion.init(center: location, latitudinalMeters: regionInMeters, longitudinalMeters: regionInMeters)
            mapView.setRegion(region, animated: true)
        }
    }
    func checkLocationServices() {
        if CLLocationManager.locationServicesEnabled() {
            setupLocationManager()
            checkLocationAuthorrization()
        } else {
            // Show alert letting the user know they have to turn this on.
        }
    }


    func checkLocationAuthorrization() {
        switch CLLocationManager.authorizationStatus() {
        case .authorizedWhenInUse:
            mapView.showsUserLocation = true
            centerViewOnUserLocation()
            locationManager.startUpdatingLocation()
            break
        case .denied:
            // Show alret instructing them how to turn on permissions
            break
        case .notDetermined:
            break
        case .restricted:
            // Show alret letting them know what's up
            break
        case .authorizedAlways:
            break
        }
    }
}




extension ViewController: CLLocationManagerDelegate {

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        guard let location = locations.last else { return }
        let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
        let region = MKCoordinateRegion.init(center: center, latitudinalMeters: regionInMeters, longitudinalMeters: regionInMeters)
        mapView.setRegion(region, animated: true)
    }


    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        checkLocationAuthorrization()
    }
}

Answer 1

您必须在 Info.plist 文件中添加以下权限

<key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>Usage Description</string>

<key>NSLocationAlwaysUsageDescription</key>
<string>Usage Description</string>

<key>NSLocationWhenInUseUsageDescription</key>
<string>Usage Description</string>

导入库:

import MapKit
import CoreLocation

设置委托(delegate):

CLLocationManagerDelegate,MKMapViewDelegate

添加变量:

private var locationManager: CLLocationManager!
private var currentLocation: CLLocation?

在 viewDidLoad() 上编写以下代码:

    mapView.delegate = self
    mapView.showsUserLocation = true
    locationManager = CLLocationManager()
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBest

    // Check for Location Services
    if CLLocationManager.locationServicesEnabled() {
        locationManager.requestWhenInUseAuthorization()
        locationManager.startUpdatingLocation()
    }

为位置编写委托(delegate)方法:

   func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    defer { currentLocation = locations.last }

    if currentLocation == nil {
        // Zoom to user location
        if let userLocation = locations.last {
            let viewRegion = MKCoordinateRegion(center: userLocation.coordinate, latitudinalMeters: 2000, longitudinalMeters: 2000)
            mapView.setRegion(viewRegion, animated: false)
        }
    }
}

就是这样，现在您可以看到您当前的位置和蓝点。