在地图中包裹纬度和经度时崩溃答案

【问题标题】：Crash when wrapping latitude and longitude in map在地图中包裹纬度和经度时崩溃
【发布时间】：2018-08-31 00:49:15
【问题描述】：

我得到当前用户的地图位置，并以他的位置为地图中心，将其呈现在地图上。上线就崩溃了

let currentLatitude = (locationManager.location?.coordinate.latitude)!
let currentLongitude = (locationManager.location?.coordinate.longitude)!

出现错误“无法从角落 4 插入法律归属”

我认为这与纬度和经度的强制换行有关。我该怎么做才能解决这个错误？？

这是我的代码：

// Location Manager settings
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()

let currentLatitude = (locationManager.location?.coordinate.latitude)!
let currentLongitude = (locationManager.location?.coordinate.longitude)!

//Map settings
mapMyLocation.showsUserLocation = true
mapMyLocation.delegate = self
let locationcoordinates = CLLocationCoordinate2D(latitude: currentLatitude, longitude: currentLongitude)
let zoomSpan = MKCoordinateSpan(latitudeDelta: 0.5, longitudeDelta: 0.5)
let region = MKCoordinateRegion(center: locationcoordinates, span: zoomSpan)
mapMyLocation.setRegion(region, animated: true)

【问题讨论】：

标签： mapkit latitude-longitude

【解决方案1】：

试试下面的代码

    if let currentLatitude = locationManager.location?.coordinate.latitude,
        let currentLongitude = locationManager.location?.coordinate.longitude {

        //Map settings
        mapMyLocation.showsUserLocation = true
        mapMyLocation.delegate = self
        let locationcoordinates = CLLocationCoordinate2D(latitude: currentLatitude, longitude: currentLongitude)
        let zoomSpan = MKCoordinateSpan(latitudeDelta: 0.5, longitudeDelta: 0.5)
        let region = MKCoordinateRegion(center: locationcoordinates, span: zoomSpan)
        mapMyLocation.setRegion(region, animated: true)
    }

【讨论】：

我在 func locationManager(_:didUpdateLocations locations:) 中使用了您的代码，而不是 viewdidLoad，它现在对我来说很好用。非常感谢。