swift - CLLocation + 天气(Alamofire)问题

Question

我正在尝试使用 CLLocation 来捕获经度和纬度，然后使用 Alamofire 中的经度和纬度来获取天气。每次，经度和纬度都不会停止更新，也不会打印天气数据(如果你想查看这里是数据的示例链接:http://forecast.weather.gov/MapClick.php?lat=37.33233141&lon=-122.0312186&FcstType=json)

class SampleViewController: UIViewController, CLLocationManagerDelegate {
var locationManager:CLLocationManager!
var startLocation: CLLocation!
var isFetchingWeather = false

override func viewDidLoad() {
    super.viewDidLoad()
    locationManager = CLLocationManager()
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestAlwaysAuthorization()
   }

     override func viewDidAppear(_ animated: Bool) {
            getCurrentLocation()
     }
   func getCurrentLocation(){
    if CLLocationManager.locationServicesEnabled(){
        locationManager.startUpdatingLocation()

    }
}

     func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        var userLocation:CLLocation = locations[0]
        if isFetchingWeather != false{
    print("user latitude = \(userLocation.coordinate.latitude)")
    print("user longitude = \(userLocation.coordinate.longitude)")
    let requestLink = "http://forecast.weather.gov/MapClick.php?lat=\(userLocation.coordinate.latitude)&lon=\(userLocation.coordinate.longitude)&FcstType=json"
    print(requestLink)
    Alamofire.request(requestLink).validate().responseJSON
        { response in
            switch response.result {
            case .success(let data):
                let json = JSON(data)
                self.weatherData = json["data"].arrayValue
                    for weather in self.weatherData{
                    let temp = weather["weather"].stringValue
                       self.weatherString.append(temp)
                }
                print (self.weatherString)
                if self.startLocation == nil {
                    self.startLocation = userLocation as! CLLocation
                    self.locationManager.stopUpdatingLocation()
                }


            case .failure(let error):
                print(error)
            }
    }
        }
        else{
            print("is fetching weather is false")
        }

}


func locationManager(_ manager: CLLocationManager, didFailWithError error: Error)
{
    print("Error \(error)")
}
}

谢谢。

Answer 1

你真的不应该在你的位置委托(delegate)中运行你的天气请求。相反，在 didUpdateLocations 委托(delegate)中获取您的位置并将其保存到 var。接下来，调用 stopUpdatingLocation()，然后调用一个单独的函数来发出天气请求。像这样:

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {

    let newLocation = locations.last

//check accuracy and timestamp of location to make sure its not a cached/old location (if you don't care about accuracy or time, you can remove this check)
    let timeDiff = newLocation?.timestamp.timeIntervalSinceNow

    if timeDiff < 5.0 && (newLocation?.horizontalAccuracy)!<=self.accuracyNeeded{

        //stop updating location
        self.locationManager.stopUpdatingLocation()

        //set currentUserLocation
        self.myLocation=newLocation?.coordinate


        //call function to get weather

        //remove delegate
        self.locationManager.delegate = nil

    }

}