CLLocationManager fatal error: unexpectedly found nil while unwrapping an Optional value Swift

Question

I have a problem because my app crash when i try to get position user and have permission in my .plist this my code.

import UIKit
import MapKit
import CoreLocation

class mapClass : UIViewController,MKMapViewDelegate,CLLocationManagerDelegate{

    var location4 = CLLocation()
    var lm  = CLLocationManager ()

    @IBOutlet  var propMapa: MKMapView!

    lm.delegate=self
    lm.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
    lm.distanceFilter = kCLDistanceFilterNone
    lm.startUpdatingLocation()

    println("\(lm.location)") <---- nil

   location4 = lm.location <---- crash

}

Log: fatal error: unexpectedly found nil while unwrapping an Optional value

Answer 1

After calling lm.startUpdatingLocation() the location manager calls didUpdateLocations() whenever it detects a location change, so you need to implement CLLocationManager::didUpdateLocations to retrieve the location:

import UIKit
import MapKit
import CoreLocation

class mapClass : UIViewController,MKMapViewDelegate,CLLocationManagerDelegate{

    var location4 = CLLocation()
    var lm  = CLLocationManager ()

    @IBOutlet  var propMapa: MKMapView!

    ...

    lm.delegate=self
    lm.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
    lm.distanceFilter = kCLDistanceFilterNone
    lm.startUpdatingLocation()
}

func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {

    let currentLocation = locations.last as CLLocation
    println(currentLocation)
    ...
}