Question

如何在viewDidLoad方法中引用用户当前的纬度和经度值？

我尝试过使用以下内容，但是......

   let locationManager = CLLocationManager()

    override func viewDidLoad()    
{
        super.viewDidLoad()

        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        self.locationManager.requestWhenInUseAuthorization()
        self.locationManager.startUpdatingLocation()

        self.mapView.showsUserLocation = true
        mapView.delegate = self
        let locationLong = locationManager.location!.coordinate.longitude
        ...

我不认为locationManager在代码运行之前有机会获取该值，并且它失败并显示消息：

致命错误：在解包可选值时意外发现nil

Answer 1

我找到了我在这里寻找的答案：

Nil when obtain coordinates in swift

作为一般规则，除非启动位置服务并且已经开始进行位置更新（例如，您已经看到调用了didUpdateLocations），否则您不应期望位置属性的有效CLLocation对象。确定位置的过程是异步发生的，并且预计在viewDidLoad中不可用。应该将特定于位置的逻辑放在didUpdateLocations方法中。

Answer 2

请尝试以下代码。希望这对你有用。感谢

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    locationManager = CLLocationManager()
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestAlwaysAuthorization()
    locationManager.startUpdatingLocation()

    self.mapView.showsUserLocation = true
    mapView.delegate = self
}

// CLLocationManager Delegate Method
func locationManager(manager:CLLocationManager, didUpdateLocations locations:AnyObject[]) {
      //Use manager for latitude and longitude
}

用户在ViewDidLoad中拉长

2 个答案: