ios - Swift:谷歌地图代码抛出零异常

Question

我有以下代码，它基本上应该检测位置(如果位置服务打开)，然后返回到上一页并显示坐标(单击按钮时)。

@IBOutlet var mapView:GMSMapView!//在 Storyboard 上添加 Google map 检查 var locationManager: CLLocationManager! 变种 View Controller : View Controller !//保存前一个 Controller 的对象以将位置发回

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    locationManager = CLLocationManager() // Intialize the location manager
    locationManager.delegate = self

}


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

//Methos to change the MApType
@IBAction func changeMaptoEarthView()
{
    self.mapView.mapType = kGMSTypeSatellite
}

@IBAction func changeMaptoMapView()
{
    self.mapView.mapType = kGMSTypeNormal
}
//Method to get UserLocation
@IBAction func sendLocationtoPreviousView()
{
    viewController.locationRecieved(locationManager.location)
    self.performSegueWithIdentifier("backSegue", sender: nil)
}

@IBAction func addUserLocation() //Detect location click event
{
    if(CLLocationManager.authorizationStatus() == .AuthorizedWhenInUse) // If already have location access
    {
        locationManager.startUpdatingLocation()
    }
    else if (CLLocationManager.authorizationStatus() == .Denied)// If location access is denied in setting
    {
        UIAlertView(title: "Permission", message: "Please allow location services in setting", delegate: nil, cancelButtonTitle: "ok").show()
    }
    else
    {
        locationManager.requestWhenInUseAuthorization() // Ask user permission if permission not given
    }
}

//CLLocation Manager Delegate methoda
func locationManager(manager: CLLocationManager!, didChangeAuthorizationStatus status: CLAuthorizationStatus) {

    if status == .AuthorizedWhenInUse {

        locationManager.startUpdatingLocation()

    }
}


func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
    if let location = locations.first as? CLLocation {

        self.mapView.clear() // clear all overlay on Map
        self.mapView.camera = GMSCameraPosition(target: location.coordinate, zoom: 15, bearing: 0, viewingAngle: 0)
        // Adding pin on Current location
        var marker = GMSMarker()
        marker.position = location.coordinate
        marker.snippet = "My Location"
        marker.appearAnimation = kGMSMarkerAnimationPop
        marker.map = mapView

        locationManager.stopUpdatingLocation()
    }
}

该应用程序在模拟器中运行，直到我说返回，然后它在这一行抛出 nil 错误消息:

    viewController.locationRecieved(locationManager.location)

可能是什么原因？我可以在 map 上看到图钉，尽管 map 上除了下面的谷歌 Logo 外没有显示任何图形

Answer 1

如果您在 View (GMSMapView 的子类)中看不到 map 图形，这是因为 Google map API key ，可能您尚未在您的应用委托(delegate)中设置它，或者它设置不正确!

确保您已使用您的应用程序包 ID 和您在 google 中的帐户设置了正确的 google API key 。您必须在您的应用删除中设置以下代码，执行 didFinishLaunchingWithOptions 功能:

import GoogleMaps

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
          GMSServices.provideAPIKey("your API Key")
}