Swift - CLGeocoder reverseGeocodeLocation completionHandler closure

With these lines of Swift, you can print out fully the location's address:

func getLocationAddress(location:CLLocation) {
    var geocoder = CLGeocoder()

    println("-> Finding user address...")

    geocoder.reverseGeocodeLocation(location, completionHandler: {(placemarks, error)->Void in
        var placemark:CLPlacemark!

        if error == nil && placemarks.count > 0 {
            placemark = placemarks[0] as CLPlacemark

            var addressString : String = ""
            if placemark.ISOcountryCode == "TW" /*Address Format in Chinese*/ {
                if placemark.country != nil {
                    addressString = placemark.country
                }
                if placemark.subAdministrativeArea != nil {
                    addressString = addressString + placemark.subAdministrativeArea + ", "
                }
                if placemark.postalCode != nil {
                    addressString = addressString + placemark.postalCode + " "
                }
                if placemark.locality != nil {
                    addressString = addressString + placemark.locality
                }
                if placemark.thoroughfare != nil {
                    addressString = addressString + placemark.thoroughfare
                }
                if placemark.subThoroughfare != nil {
                    addressString = addressString + placemark.subThoroughfare
                }
            } else {
                if placemark.subThoroughfare != nil {
                    addressString = placemark.subThoroughfare + " "
                }
                if placemark.thoroughfare != nil {
                    addressString = addressString + placemark.thoroughfare + ", "
                }
                if placemark.postalCode != nil {
                    addressString = addressString + placemark.postalCode + " "
                }
                if placemark.locality != nil {
                    addressString = addressString + placemark.locality + ", "
                }
                if placemark.administrativeArea != nil {
                    addressString = addressString + placemark.administrativeArea + " "
                }
                if placemark.country != nil {
                    addressString = addressString + placemark.country
                }
            }

            println(addressString)
        }
    })
}

Cheers!


I found the answer I needed in this thread: Set address string with reverseGeocodeLocation: and return from method

The issue lies with the fact that reverseGeocodeLocation is asynchronous, the method is returning a value before the completionBlock sets p in my example.


As requested, here's my current code.

func showAddViewController(placemark:CLPlacemark){
    self.performSegueWithIdentifier("add", sender: placemark) 
}

func getPlacemarkFromLocation(location: CLLocation){
    CLGeocoder().reverseGeocodeLocation(location, completionHandler:
        {(placemarks, error) in
            if error {println("reverse geodcode fail: \(error.localizedDescription)")}
            let pm = placemarks as [CLPlacemark]
            if pm.count > 0 { self.showAddPinViewController(placemarks[0] as CLPlacemark) }
    })
}

I didn't want to take the NSNotificationCenter route because that would add unnecessary overhead, rather inside the completionHandler closure I call upon another function and pass the CLPlacemark generated by getPlacemarkFromLocation as a parameter to keep things asynchronous since the function will be called after placemarks is set the function (should) receive the placemark needed and execute the code you want. Hope what I said makes sense.


Here is closure that worked for me -- it took awhile to get it to work. I think your problem is related to not initializing p with the correct initializer. I tried a few variations until I got this to work: self.placemark = CLPlacemark(placemark: stuff[0] as CLPlacemark)

geocoder.reverseGeocodeLocation(newLocation, completionHandler: {(stuff, error)->Void in

        if error {
            println("reverse geodcode fail: \(error.localizedDescription)")
            return
        }

        if stuff.count > 0 {
            self.placemark = CLPlacemark(placemark: stuff[0] as CLPlacemark)

            self.addressLabel.text = String(format:"%@ %@\n%@ %@ %@\n%@",
                self.placemark.subThoroughfare ? self.placemark.subThoroughfare : "" ,
                self.placemark.thoroughfare ? self.placemark.thoroughfare : "",
                self.placemark.locality ? self.placemark.locality : "",
                self.placemark.postalCode ? self.placemark.postalCode : "",
                self.placemark.administrativeArea ? self.placemark.administrativeArea : "",
                self.placemark.country ? self.placemark.country : "")
        }
        else {
            println("No Placemarks!")
            return
        }

        })

EDIT:

moved better answer to its own answer.