如何使“地圖上的中心位置”起作用？

Question

我是編程新手。 我在下面找到了代碼，除了中心位置外，它還能執行所有操作。（放大，地圖，藍點均可用。）如果我在模擬器中運行，（城市運行）藍點僅在頁面外運行。

import UIKit
import MapKit
import CoreLocation
import Foundation

class ViewController: UIViewController, CLLocationManagerDelegate {
    @IBOutlet weak var map: MKMapView!

    var locationManager: CLLocationManager?

    override func viewDidLoad() {
        super.viewDidLoad()

        locationManager = CLLocationManager()
        locationManager!.delegate = self

        map.showsUserLocation = true

        if CLLocationManager.authorizationStatus() == .authorizedWhenInUse {
            locationManager!.startUpdatingLocation()
        } else {
            locationManager!.requestWhenInUseAuthorization()
        }
    }

    private func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
        switch status {
        case .notDetermined:
            print("NotDetermined")
        case .restricted:
            print("Restricted")
        case .denied:
            print("Denied")
        case .authorizedAlways:
            print("AuthorizedAlways")
        case .authorizedWhenInUse:
            print("AuthorizedWhenInUse")
            locationManager!.startUpdatingLocation()
        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        let location = locations.first!
        let coordinateRegion = MKCoordinateRegionMakeWithDistance(location.coordinate, 500, 500)
        map.setRegion(coordinateRegion, animated: true)
        locationManager?.stopUpdatingLocation()
        locationManager = nil
    }
}

Answer 1

刪除您的實施

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

只要獲得授權，設置map.showsUserLocation = true ，然后退后map.showsUserLocation = true 。

Answer 2

這是我的Swift 3代碼，可以正常工作並經過測試。 它會加載mapView，征求用戶的許可並放大其位置。

import UIKit
import MapKit

class ViewController: UIViewController, CLLocationManagerDelegate {
@IBOutlet weak var mapView: MKMapView!

let locationManager = CLLocationManager()

override func viewDidLoad() {
    super.viewDidLoad()
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
    locationManager.activityType = .automotiveNavigation
    locationManager.distanceFilter = 10.0
    mapView.showsUserLocation = true
    mapView.mapType = .standard
    self.mapView.delegate = self
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    locationManager.requestWhenInUseAuthorization()
    locationManager.startUpdatingLocation()
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    let userLocation:CLLocation = locations[0] as CLLocation
    locationManager.stopUpdatingLocation()
    let location = CLLocationCoordinate2D(latitude: userLocation.coordinate.latitude, longitude: userLocation.coordinate.longitude)
    let span = MKCoordinateSpanMake(0.05, 0.05)
    let region = MKCoordinateRegion (center:  location,span: span)       
    mapView.setRegion(region, animated: true)
}
}