MapKit 缩放到用户当前位置
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【中文标题】MapKit 缩放到用户当前位置【英文标题】：MapKit zoom to user current location 【发布时间】：2017-05-02 12:44:18 【问题描述】：我试图简单地在地图上显示用户的位置，但我需要在应用程序启动时，地图应该缩放到当前位置，但我不知道为什么地图根本不缩放，就像这样：
代码如下：
class MapViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate
@IBOutlet weak var mapView: MKMapView!
var locationManager = CLLocationManager()
override func viewDidLoad()
super.viewDidLoad()
mapView.delegate = self
mapView.showsUserLocation = true
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.requestWhenInUseAuthorization()
locationManager.delegate = self
DispatchQueue.main.async
self.locationManager.startUpdatingLocation()
func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!)
let location = locations.last as! CLLocation
let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
var region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.1, longitudeDelta: 0.1))
region.center = mapView.userLocation.coordinate
mapView.setRegion(region, animated: true)
【问题讨论】：
删除region.center = mapView.userLocation.coordinate
@shallowThought 我做了，但没有任何改变
【参考方案1】：
我遇到了类似的问题，浪费了 4 天时间思考出了什么问题。最后通过在viewDidLoad 方法中创建这些代码行来解决：
//Zoom to user location
let noLocation = CLLocationCoordinate2D()
let viewRegion = MKCoordinateRegionMakeWithDistance(noLocation, 200, 200)
mapView.setRegion(viewRegion, animated: false)
mapView.showsUserLocation = true
在ViewDidLoad 方法中添加这些新的更改代码：
override func viewDidLoad()
super.viewDidLoad()
let locationManager = CLLocationManager()
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
// Check for Location Services
if (CLLocationManager.locationServicesEnabled())
locationManager.requestAlwaysAuthorization()
locationManager.requestWhenInUseAuthorization()
//Zoom to user location
if let userLocation = locationManager.location?.coordinate
let viewRegion = MKCoordinateRegionMakeWithDistance(userLocation, 200, 200)
mapView.setRegion(viewRegion, animated: false)
self.locationManager = locationManager
DispatchQueue.main.async
self.locationManager.startUpdatingLocation()
希望这有助于解决您的问题。如果有任何进一步的问题，请随时发表评论。谢谢
【讨论】：
此代码 sn-p 失败，因为 locationManager 在第一次调用时未初始化。远程线路：locationManager.desiredAccuracy = kCLLocationAccuracyBest locationManager.delegate = self 为什么locationManager.requestWhenInUseAuthorization() 行重复？
如果你再读一遍它会有两个不同的想法：requestWhenInUseAuthorization 和 requestAlwaysAuthorization
为了放大用户位置，需要在上面的代码中进行更改。 -> 让 noLocation = locationManager.location?.coordinate
@ViruMax 我觉得为时已晚，但您需要添加mapView.showsUserLocation = true 才能看到蓝色圆圈。【参考方案2】：
这是 Swift 3，XCode 8.2 的另一种方法。首先，写出一个辅助函数：
let homeLocation = CLLocation(latitude: 37.6213, longitude: -122.3790)
let regionRadius: CLLocationDistance = 200
func centerMapOnLocation(location: CLLocation)
let coordinateRegion = MKCoordinateRegionMakeWithDistance(location.coordinate,
regionRadius * 2.0, regionRadius * 2.0)
mapView.setRegion(coordinateRegion, animated: true)
然后，拨打viewDidLoad()
mapView.showsUserLocation = true
centerMapOnLocation(location: homeLocation)
这将使用放大的变量中指定的位置启动应用程序。
【讨论】：
如果homeLocation能被代码自动找到会更有帮助。【参考方案3】：
在 Swift 4.2 中，此代码发生了变化。下面是它现在的工作方式：
import UIKit
import MapKit
import CoreLocation
class MapVC: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate
@IBOutlet weak var mapView: MKMapView!
var locationManager = CLLocationManager()
let authorizationStatus = CLLocationManager.authorizationStatus()
let regionRadius: Double = 1000
override func viewDidLoad()
super.viewDidLoad()
mapView.delegate = self
locationManager.delegate = self
configureLocationServices()
func centerMapOnUserLocation()
guard let coordinate = locationManager.location?.coordinate else return
let coordinateRegion = MKCoordinateRegion(center: coordinate, latitudinalMeters: regionRadius, longitudinalMeters: regionRadius)
mapView.setRegion(coordinateRegion, animated: true)
func configureLocationServices()
if authorizationStatus == .notDetermined
locationManager.requestAlwaysAuthorization()
else
return
func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus)
centerMapOnUserLocation()
【讨论】：
您可能希望使用CLLocationDistance 类型来代替regionRadius【参考方案4】：
代码：
import UIKit
import MapKit
class ViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate
@IBOutlet weak var mapview: MKMapView!
let locationmanager = CLLocationManager()
override func viewDidLoad()
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
mapview.mapType = MKMapType.standard
let location = CLLocationCoordinate2DMake(22.4651, 70.0771)
let span = MKCoordinateSpanMake(0.5, 0.5)
let region = MKCoordinateRegionMake(location, span)
mapview.setRegion(region, animated: true)
let annonation = MKPointAnnotation()
annonation.coordinate = location
annonation.title = "Chandi Bazar"
annonation.subtitle = "Jamnagar"
//
mapview.addAnnotation(annonation)
self.locationmanager.requestWhenInUseAuthorization()
if CLLocationManager.locationServicesEnabled()
locationmanager.delegate = self
locationmanager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
locationmanager.startUpdatingLocation()
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
let locValue:CLLocationCoordinate2D = manager.location!.coordinate
print("locations = \(locValue.latitude) \(locValue.longitude)")
locationmanager.stopUpdatingLocation()
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView?
if (annotation is MKUserLocation)
return nil
let annotationidentifier = "Annotationidentifier"
var annotationview:MKAnnotationView
annotationview = MKAnnotationView(annotation: annotation, reuseIdentifier: annotationidentifier)
let btn = UIButton(type: .detailDisclosure)
btn.addTarget(self, action: #selector(ViewController.hirenagravat(sender:)), for: .touchUpInside)
annotationview.rightCalloutAccessoryView = btn
annotationview.image = UIImage(named: "images (4).jpeg")
annotationview.canShowCallout = true
return annotationview
func hirenagravat(sender:UIButton)
let fvc = storyboard?.instantiateViewController(withIdentifier: "secondViewController") as? secondViewController
self.navigationController?.pushViewController(fvc!, animated: true)
【讨论】：
【参考方案5】：当您设置区域时 -> 您无法再缩放地图。下面来解决这个问题
func yourFuncName()
//this is global var
regionHasBeenCentered = false
if !self.regionHasBeenCentered
let span: MKCoordinateSpan = MKCoordinateSpanMake(0.01, 0.01)
let userLocation: CLLocationCoordinate2D = CLLocationCoordinate2DMake(_cllocationOfUserCurrentLocation!.coordinate.latitude, _cllocationOfUserCurrentLocation!.coordinate.longitude)
let region: MKCoordinateRegion = MKCoordinateRegionMake(userLocation, span)
self.mapView.setRegion(region, animated: true)
self.regionHasBeenCentered = true
self.mapView.showsUserLocation = true
【讨论】：
【参考方案6】：尝试使用 MKMapViewDelegate 函数：
var isInitiallyZoomedToUserLocation: Bool = false
func mapView(_ mapView: MKMapView, didUpdate userLocation: MKUserLocation)
if !isInitiallyZoomedToUserLocation
isInitiallyZoomedToUserLocation = true
mapView.showAnnotations([userLocation], animated: true)
【讨论】：
同意这个，已经有位置权限的就不用加CLLocationManager了 我们可以使用 setRegion 来代替 showAnnotations()，因为我们现在可以访问 userLocation。让 viewRegion = MKCoordinateRegion(center: userLocation.coordinate, latitudinalMeters: 200, verticalMeters: 200) mapView.setRegion(viewRegion, animated: true)【参考方案7】：在 swift 4.1 中。要更改缩放级别，您需要更改跨度值，即 MKCoordinateSpan(latitudeDelta: 0.95, longitudeDelta: 0.95)
let lat = "33.847105"
let long = "-118.2673272"
let region = MKCoordinateRegion(center: CLLocationCoordinate2D(latitude: Double(lat)!, longitude: Double(long)!), span: MKCoordinateSpan(latitudeDelta: 0.95, longitudeDelta: 0.95))
DispatchQueue.main.async
self.mapView.setRegion(region, animated: true)
Swift 5.0
let span = MKCoordinateSpan.init(latitudeDelta: 0.01, longitudeDelta:
0.01)
let coordinate = CLLocationCoordinate2D.init(latitude: 21.282778, longitude: -157.829444) // provide you lat and long
let region = MKCoordinateRegion.init(center: coordinate, span: span)
mapView.setRegion(region, animated: true)
【讨论】：
【参考方案8】：func animateToUserLocation()
if let annoation = mapView.annotations.filter ( $0 is MKUserLocation ).first
let coordinate = annoation.coordinate
let viewRegion = MKCoordinateRegion(center: coordinate, latitudinalMeters: 200, longitudinalMeters: 200)
mapView.setRegion(viewRegion, animated: true)
【讨论】：
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