Swift 4 CLLocationManager问题：我可以在ViewDidLoad函数中使用从CLLocationManager获取的location吗？

Question

按照网上的说明，我能够使用 CLLocationManager 获取我的当前位置。代码结构如下：

var myCurCoordinate:String!

override func viewDidLoad() {
        super.viewDidLoad()
        getLocation()
       print(myCurCoordinate) // HERE I GOT "nil". In my original code, I am not really printing it. Instead, I have another function here that needs to use myCurCoordinate
}

func getLocation() {
        locationManager = CLLocationManager()
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
        locationManager.requestAlwaysAuthorization()

        if CLLocationManager.locationServicesEnabled() {
            locationManager.startUpdatingLocation()
        }
    }
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    let loc:CLLocation = locations[0] as CLLocation
    myCurCoordinate="\(loc.coordinate.latitude),\(loc.coordinate.longitude)"
    print(myCurCoordinate) // HERE print 3 times because of its async
}

任何人都可以帮我弄清楚如何获取位置信息并能够在 viewDidLoad() 中打印它吗？

谢谢！

Answer 1

您无法在 viewDidLoad 中打印您的位置，因为它是一种异步方法，您需要等到它被获取。当您获得您的位置时，您需要停止使用 stopUpdatingLocation() 更新您的位置。为此，我更喜欢使用以下内容。

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if let location = locations.last {
        initialLocation = CLLocation(latitude: location.coordinate.latitude,
                                     longitude: location.coordinate.longitude)
        print(initialLocation)
        getLocation?(initialLocation)
    }
    manager.stopUpdatingLocation()
}

如果你坚持要在里面打印它 viewDidLoad() 你可以用闭包来完成。首先，你需要定义一个闭包。

var getLocation: ((_ location: CLLocation) -> (Void))?

然后在您的 viewDidLoad() 方法中，您需要指定触发闭包时要执行的操作。

 getLocation = { location in
        print(location)
    }

然后你需要使用

在 didUpdateLocations 中触发关闭

getLocation?(initialLocation)

Swift 4 CLLocationManager问题：我可以在ViewDidLoad函数中使用从CLLocationManager获取的location吗？

Swift 4 CLLocationManager question: Can I use the location, which is got from CLLocationManager, in ViewDidLoad function?

swift

swift4