iOS 9 [locationManager.requestWhenInUseAuthorization()] alert视图出现后很快消失

Question

我配置了一个非常基本的应用程序。它使用导航控制器，以及我配置为地图视图控制器的视图控制器。

当应用程序启动时，它启动到根视图控制器，从那里，我有一个按钮配置为继续到地图视图控制器并显示地图。发生这种情况时，将显示警报视图，但在我 select allow/don 不允许之前，它会消失并加载地图。

为什么警报视图会自行消失？

我已经相应地配置了 info.plist 文件，添加了必要的框架并添加了适当的委托。

下面是我配置的代码：

import UIKit
import MapKit
import CoreLocation


class ViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate {

@IBOutlet weak var map: MKMapView!

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

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

}


func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {

    let userLocation = locations[0]

    let latitude = userLocation.coordinate.latitude
    let longitude = userLocation.coordinate.longitude
    let latDelta: CLLocationDegrees = 0.01
    let lonDelta: CLLocationDegrees = 0.01
    let coordinate: CLLocationCoordinate2D = CLLocationCoordinate2DMake(latitude, longitude)
    let span: MKCoordinateSpan = MKCoordinateSpanMake(latDelta, lonDelta)
    let region: MKCoordinateRegion = MKCoordinateRegionMake(coordinate, span)
    map.setRegion(region, animated: true)
}

func locationManager(manager: CLLocationManager, didFailWithError error: NSError) {
    print(error)
}

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


}

任何帮助将不胜感激！提前致谢！

Answer 1

在 viewDidLoad 之外声明您的 locationManager ivar。它在 viewDidLoad 完成后被释放，因为没有任何东西对它有强引用。您可能还应该只在您的用户授予访问权限后才开始扫描。

var locationManager:CLLocationManager!

override func viewDidLoad() {
  super.viewDidLoad()

  locationManager = CLLocationManager()
  locationManager.delegate = self
  locationManager.desiredAccuracy = kCLLocationAccuracyBest
  let authorizationStatus = CLLocationManager.authorizationStatus()
    if (authorizationStatus == CLAuthorizationStatus.NotDetermined) {
      locationManager.requestWhenInUseAuthorization()
    } else if (authorizationStatus == CLAuthorizationStatus.AuthorizedWhenInUse) {
      locationManager.startUpdatingLocation()
    }
}

func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
  if (status == CLAuthorizationStatus.AuthorizedWhenInUse) {
    locationManager.startUpdatingLocation()
  }

}

Answer 2

因为你做错了。 CLLocationManagerDelegate 协议有一个名为 didChangeAuthorizationStatus 的方法。您应该在那里检查用户是否允许该应用程序使用位置。检查之后，您应该调用 startUpdatingLocation。请务必在主队列上也使用 dispatch_async 执行此代码所需的所有 UI 更新。

iOS 9 [locationManager.requestWhenInUseAuthorization()] alert视图出现后很快消失

iOS 9 [locationManager.requestWhenInUseAuthorization()] alert view disappears quickly after appearing

core-location

mapkit

ios

swift