从 CLLocationManager (Google Maps API) 获取用户位置的问题答案

【问题标题】：Issues getting user location from CLLocationManager (Google Maps API)从 CLLocationManager (Google Maps API) 获取用户位置的问题
【发布时间】：2017-02-15 23:16:53
【问题描述】：

我正在开发一个使用 Google Maps API 的 iPhone 应用程序，但在获取用户的当前位置时遇到问题，以便地图在他们的位置上打开。

我现在已经花了几天的时间来解决编译器错误，但它仍然不能正常工作。地图显示了，但仅在我为 long 和 lat 变量提供的初始坐标处。我认为这与CLLoationManager() 有关。

在模拟器上更新位置没有任何结果，我觉得我犯了一个菜鸟错误，我只是不知道是什么。和建议？

    import UIKit
    import CoreLocation
    import GoogleMaps


class ViewController: UIViewController, CLLocationManagerDelegate {

var long:Double = -0.13
var lat:Double = 51.0

let locationManager = CLLocationManager()

override func loadView() {
    // Create a GMSCameraPosition that tells the map to display the

    //user location stuff
    self.locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestAlwaysAuthorization()
    locationManager.startUpdatingLocation()


    let camera = GMSCameraPosition.camera(withLatitude: CLLocationDegrees(lat), longitude: CLLocationDegrees(long), zoom: 5.0)
    let mapView = GMSMapView.map(withFrame: CGRect.zero, camera: camera)

    view = mapView
    mapView.showUserLocation = true
    // Creates a marker in the center of the map.
    let marker = GMSMarker()
    marker.position = CLLocationCoordinate2D(latitude: 51.51 , longitude: -0.13)
    marker.title = "Test"
    marker.snippet = "This is a test"
    marker.map = mapView
}

func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) { //i think this is the problem area
    let userLocation = locations.last!
    long = userLocation.coordinate.longitude
    lat = userLocation.coordinate.latitude

    self.locationManager.stopUpdatingLocation()

}
}

【问题讨论】：

标签： swift google-maps-api-3 core-location cllocationmanager user-location

【解决方案1】：

当您获得用户的位置时，您并没有更新地图的当前位置。您需要执行以下操作：

// property to store map view instead of just a local variable in loadView()
var mapView: GMSMapView?

func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) { //i think this is the problem area
    let userLocation = locations.last!
    long = userLocation.coordinate.longitude
    lat = userLocation.coordinate.latitude

    let newCamera = GMSCameraPosition.camera(withLatitude: lat, longitude: long)
    mapView.camera = newCamera
    self.locationManager.stopUpdatingLocation()

}

【讨论】：