swift - 如何将 var 值设置为当前的纬度或经度？ nikhil 提供的更新代码

Question

我需要在类之外访问这些坐标值，以便计算某些方程，但是当我尝试将 myLat 分配给 UserCooperatives.userLat 或 UserCooperatives.userLong 时，会发生错误。

我尝试过使用结构和类以及全局变量，但都返回了各种错误。

    public class UserCoordinates {
        static let  shared:UserCoordinates = UserCoordinates()
        var userLat: Double?
        var userLong: Double?

        func setUserLat(userLat: Double, userLong: Double) {
            self.userLong = userLong
            self.userLat = userLat
        }
        private init() {

        }
        func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]){
            guard let location = locations.last else {
                return
            }
            userLat = Double(location.coordinate.latitude)
            userLong = Double(location.coordinate.longitude)
        }

    }

sin(my latitude)
I want to take the sin of my latitude wherever I am how would I assign the value of userLat in the class/function to this sin calculation?

Answer 1

除非变量是静态的，否则不能使用类直接访问变量。如果您希望某些东西成为一个实例，那么您应该使用单例检查下面的代码。

public class UserCoordinates {
    static let  shared:UserCoordinates = UserCoordinates()
    var userLat: Double?
    var userLong: Double?

    func setUserLat(userLat: Double, userLong: Double) {
        self.userLong = userLong
        self.userLat = userLat
    }
    private init() {

    }
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]){
        guard let location = locations.last else {
            return
        }
        userLat = Double(location.coordinate.latitude)
        userLong = Double(location.coordinate.longitude)
    }

}
UserCoordinates.shared.setUserLat(userLat: 10.0, userLong: 10.0)
let myLat = UserCoordinates.shared.userLat