Question

我编写了一个程序，该程序使用LocationManagerDelegate在当前位置更改时在调试区域中显示坐标。检索坐标时出错

不能在属性初始化程序中使用实例成员“ locationManager”；属性初始化程序在“自我”可用之前运行

import UIKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate{

var locationManager: CLLocationManager!

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

   setUpLocationManager()
}

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

func setUpLocationManager() {
    locationManager = CLLocationManager()
    guard let locationManager = locationManager else {return}
    locationManager.requestWhenInUseAuthorization()
    let status = CLLocationManager.authorizationStatus()
    if status == .authorizedWhenInUse {
        locationManager.delegate = self
        locationManager.distanceFilter = 10
        locationManager.startUpdatingLocation()
        printLocation()
    }
}


func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) ->Optional<Any> {
    let location = locations.first
    let latitude = location?.coordinate.latitude
    let longitude = location?.coordinate.longitude
    let latlong = [latitude, longitude]
    return latlong
}
let myLocation = locationManager()

func printLocation() {
    print("test\(myLocation)")
}

}

测试（功能）输出

let myLocation = locationManager ()

更改为

let myLocation = locationManager

Answer 1

您的代码包含一些错误。

发生错误是因为您不能在类的顶层执行受影响的行。

首先，您不得更改委托方法的签名。此 custom 委托方法

public static void main(String []args){
    byte b = 6;
    b=b+8;
    //b+=8;
    System.out.println(b);
    b+=7;
    System.out.println(b);
}

将从不被呼叫。

此外，为什么您应该将返回类型声明为func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) ->Optional<Any> { ...，尽管应该将其声明为Any?？

立即创建位置管理器，替换

[CLLocationCoordinate2D]

使用

var locationManager: CLLocationManager!

在let locationManager = CLLocationManager()中删除行

~~setUpLocationManager()~~
委托方法locationManager = CLLocationManager() guard let locationManager = locationManager else {return} // this line is completely pointless anyway printLocation()定期且异步调用。在方法内部打印结果
```
didUpdateLocations
```

删除

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) { guard let location = locations.first else { return } let latitude = location.coordinate.latitude let longitude = location.coordinate.longitude let latlong = [latitude, longitude] print("test", latlong) }

我想取出代表中获取的坐标

1 个答案: