使用 CLLocationManager 获取用户位置时出错

Question

我正在使用集合视图和集合视图可重用标题。在标题中，我试图获取用户的位置。我不断收到此错误：

   Trying to start MapKit location updates without prompting for    
   location authorization. Must call -[CLLocationManager    
   requestWhenInUseAuthorization] or -[CLLocationManager    
   requestAlwaysAuthorization] first.

我查看了这个问题：Location Services not working in iOS 8，但没有一个建议的解决方案对我有用。我已将密钥（NSLocationAlwaysUsageDescription 和 NSLocationWhenInUseUsageDescription）添加到我的 info.Plist 中，但这并没有帮助。该应用程序从不要求用户获取其位置。这是我的代码：

编辑：我现在的代码：

   import UIKit
   import MapKit
   import Parse
   import ParseUI
   import CoreLocation

   class ReusableHeaderMap: UICollectionReusableView, CLLocationManagerDelegate {
let locationManager = CLLocationManager()

@IBOutlet weak var newMap: MKMapView!


override func awakeFromNib() {
    locationManager.delegate = self
    let status = CLLocationManager.authorizationStatus()
    if status == CLAuthorizationStatus.Denied {

    }
    else if status == CLAuthorizationStatus.NotDetermined {
        self.locationManager.requestAlwaysAuthorization()
    }
    else if status == CLAuthorizationStatus.AuthorizedAlways {
        self.locationManager.startUpdatingLocation()
    }
    else {
        print("it took the else route")

    }

    print("status is \(status)")
    self.newMap.layer.cornerRadius = 8
    self.newMap.clipsToBounds = true

}

func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if locations.count > 0 {
        locationManager.stopUpdatingLocation()
        let location1 = locations.first as CLLocation!
        let mapSpan = MKCoordinateSpan(latitudeDelta: 0.05, longitudeDelta: 0.05)
        let mapRegion = MKCoordinateRegion(center: location1.coordinate, span: mapSpan)
        self.newMap.setRegion(mapRegion, animated: true)
    }
}


func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {

    if status == CLAuthorizationStatus.Denied {
        print("there will be limited functionaliy")
    }
    else if status == CLAuthorizationStatus.AuthorizedAlways {
        self.locationManager.startUpdatingLocation()
    }
    else {
        print("it took the else route")
      }
   }


}

我的 info.plist 有这个键：

  <key>NSLocationAlwaysUsageDescription</key>
<string>Get User Location</string>

Answer 1

错误消息告诉您必须做什么。你需要打电话给

self.locationManager.requestWhenInUseAuthorization() 

或

self.locationManager.requestAlwaysAuthorization()

在您尝试启动位置管理器之前在您的代码中。该步骤是除了将 NSLocationAlwaysUsageDescription 和/或 NSLocationWhenInUseUsageDescription 键添加到 info.plist 之外。

有关更多信息，请参阅有关这些方法的文档。

（查看您发布的代码，您的设置不正确。您不能只调用requestWhenInUseAuthorization，然后立即调用startUpdatingLocation。）

正如文档所说：

当当前授权状态为 kCLAuthorizationStatusNotDetermined，此方法异步运行 并提示用户授予应用使用位置的权限 服务。

这里的关键词是异步。

您需要进行该调用，然后实现locationManager:didChangeAuthorizationStatus: 方法。如果用户授予您的应用使用位置服务的权限，将调用该方法 (didChangeAuthorizationStatus)。

您的代码应该看起来更像这样：

override func awakeFromNib() 
{
  locationManager.delegate = self
  let status = locationManager.status
  if (status == kCLAuthorizationStatusNotDetermined)
  {
    locationManager.requestWhenInUseAuthorization()
  }
  else if (status == kCLAuthorizationStatusAuthorized)
  {
    locationManager.startUpdatingLocation()
  }
  else
  {
    //Handle other error cases here.
  }
  newMap.layer.cornerRadius = 8
  newMap.clipsToBounds = true
}

optional func locationManager(_ manager: CLLocationManager,
  didChangeAuthorizationStatus status: CLAuthorizationStatus)
{
  locationManager.startUpdatingLocation()
}