ios - 将 CLLocationCoordinate2D 返回到结构

Question

我是编程新手，我的问题是如何将变量类型 CLLocationCoordinate2D 的数据返回到坐标，即结构类型。尝试开发天气应用。

我有一个结构:

struct Coordinates {
    let latitude: Double
    let longitude: Double
}

我的代码如下所示:

//getting coordinates from String
func getCoordinateFrom(address: String, completion: @escaping(_ coordinate: CLLocationCoordinate2D?, _ error: Error?) -> () ) {
                CLGeocoder().geocodeAddressString(address) { placemarks, error in
                    completion(placemarks?.first?.location?.coordinate, error)
                }
            }

//When the User type his city, coordinates have type of CLLocationCoordinate2D    
@IBAction func changeCityButtonPressed(_ sender: UIButton) {
            guard let address = textField.text else { return }
            getCoordinateFrom(address: address) { coordinate, error in
                guard let coordinate = coordinate, error == nil else { return }
                DispatchQueue.main.async {
                    print(coordinate)
                }  
            }
        }

我有一个常量，我的任务是将坐标从函数转移到这个常量。

  let coordinates = Coordinates(latitude: 00.617366, longitude: 37.617366)

问题是函数中的这些坐标是闭包的。所以我不能返回等等。我试图找到正确的答案，但没有结果。有人有一些建议/解决方案吗？

Answer 1

在这一行:

 let coordinates = Coordinates(latitude: 00.617366, longitude: 37.617366)

用var替换let

在这段代码中:

  @IBAction func changeCityButtonPressed(_ sender: UIButton) {
        guard let address = textField.text else { return }
        getCoordinateFrom(address: address) { coordinate, error in
            guard let coordinate = coordinate, error == nil else { return }
            DispatchQueue.main.async {
                print(coordinate)
            }  
        }
    }

替换为:

  guard let coordinate = coordinate, error == nil else { return }
            DispatchQueue.main.async {
                print(coordinate)
            } 

通过这个:

  guard let coordinate = coordinate, error == nil else { return }
            coordinates.latitude = coordinate.latitude
            coordinates.longitude = coordinate.longitude
            DispatchQueue.main.async {
                print(coordinate)
            } 

这就是您的坐标变量将如何更新为新的经纬度