why am I getting nil when unwrapping optional with my location manager?

Question

My goal at this moment is to use the cllocationManager with the swift weather app. But everytime I try to use location services I get the error nil when unwrapping optional (the optional is the string variable that i'm using to store the coordinates of the location I would like to get the weather for. here's my code.

 let locationManager = CLLocationManager()

// var coordinates: String = "43.855759,-79.086491" var coordinates: String?

override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib.

aivRefresh.hidden = true

self.locationManager.requestAlwaysAuthorization()

if CLLocationManager.locationServicesEnabled() {

  // creates an instance of a location manager and
  locationManager.delegate = self
  locationManager.desiredAccuracy = kCLLocationAccuracyBest
  locationManager.startUpdatingLocation()

// println("(locationManager.location.coordinate.latitude),(locationManager.location.coordinate.longitude)")

// coordinates = "(locationManager.location.coordinate.latitude),(locationManager.location.coordinate.longitude)" // getCurrentWeatherData() println(coordinates) } else { // if there location services isn't

  self.locationManager.requestAlwaysAuthorization()
}

}

func locationManager(manager: CLLocationManager!, didFailWithError error: NSError!) { println("Error! Couldn't get location\nError: (error)") }

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

var location:CLLocationCoordinate2D = manager.location.coordinate

println("\(manager.location)")

if locations != nil {

// coordinates = "(location.longitude),(location.latitude)" var coordinates = "43.835913,-79.086248" println(coordinates) } else {

  coordinates = "43.835913,-79.086248"
  println(coordinates)
}




CLGeocoder().reverseGeocodeLocation(manager.location, completionHandler: { (placemarks, error) -> Void in

  if error == nil {

    let pmarks = placemarks[0] as CLPlacemark

    self.displayLocationInfo(pmarks)
  } else {

    println("Error: \(error.localizedDescription)")
  }
})

}

// --------------------------------------------------------------------------- func displayLocationInfo(placemark: CLPlacemark) -> Void {

self.locationManager.stopUpdatingLocation()

self.lblCurrentLocation.text = "\(placemark.administrativeArea), \(placemark.locality)"

} // --------------------------------------------------------------------------- func getCurrentWeatherData() -> Void {

let baseURL = NSURL(string: "https://api.forecast.io/forecast/\(apiKey)/")
let forecastURL = NSURL(string: coordinates!, relativeToURL: baseURL)

// session object that's a singleton (only one instance possible of this object). This ensures that there won't be other creations of a session instaince.
let sharedSession = NSURLSession.sharedSession()

//creates a task that temporarely writes the information to a location on disk
let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(forecastURL!, completionHandler: { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in

  if error == nil {

    //var urlContents = NSString(contentsOfURL: location, encoding: NSUTF8StringEncoding, error: nil) This pulls all data from the url given
    let dataObject = NSData(contentsOfURL: location)

    let weatherDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject!, options: nil, error: nil) as NSDictionary

    let currentWeather = Current(weatherDictionary: weatherDictionary)

// (currentWeather.temperature - 32) * 5/9 //Celcius conversion println(currentWeather.temperature) //test

    dispatch_async(dispatch_get_main_queue(), { () -> Void in

      //add self to make it specific since it's in a closure
      self.iconView.image = currentWeather.icon!
      self.lblCurrentTemperature.text = "\((currentWeather.temperature-32)*5/9)"
      self.lblCurrentTime.text = "Last updated \(currentWeather.currentTime!)"
      self.lblCurrentHumidity.text = "\(currentWeather.humidity)"
      self.lblCurrentPercipitation.text = "\(currentWeather.precipitationProbability)"
      self.lblSummary.text = "\(currentWeather.summary)"

      //when done loading
      self.aivRefresh.stopAnimating()
      self.aivRefresh.hidden = true
      self.btnRefresh.hidden = false
    })

  }else {

    let networkIssueController = UIAlertController(title: "Error", message: "unable to load data", preferredStyle: .Alert)

    let btnOk = UIAlertAction(title: "OK", style: .Default, handler: nil)
    let btnCancel = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)

    networkIssueController.addAction(btnOk)
    networkIssueController.addAction(btnCancel)

    self.presentViewController(networkIssueController, animated: true, completion: nil)

    dispatch_async(dispatch_get_main_queue(), { () -> Void in

      self.aivRefresh.stopAnimating()
      self.btnRefresh.hidden = false
      self.aivRefresh.hidden = true


    })
  }
})

downloadTask.resume()

} // --------------------------------------------------------------------------- @IBAction func refresh() {

locationManager.startUpdatingLocation()

getCurrentWeatherData()

btnRefresh.hidden = true
aivRefresh.hidden = false

// btnRefresh.enabled = false

aivRefresh.startAnimating()

}

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Pierre Smith

Pierre Smith

why am I getting nil when unwrapping optional with my location manager?