Reverse Geocoding with Swift (weather app)

Question

Hey there,

I finished the iOS with Swift course and managed to let the weather app find and use my location (although I haven't made the app request the authorization but gave it a default value in case it would be denied for now). But I'd like to change the label with the location to the one it finds through my coordinates. After some Googling I found I have to use reverse geocoding and I tried adapting bits of code I found around the web for my purpose but I can't get it to work. Since the part of the course mentioning completionHandlers was a little blurry to me I'm quite lost. Any help ?

My vain attempt :

    func setLocationLabel() -> String! {
        if (CLLocationManager.authorizationStatus() == .NotDetermined ||
            CLLocationManager.authorizationStatus() == .Restricted ||
            CLLocationManager.authorizationStatus() == .Denied) {
                return "Alcatraz, CA"
        } else {
            var locationCoordinates = getLocationCoordinates()
            var geocoder = CLGeocoder()
            var locationCLLocation = CLLocation(latitude: locationCoordinates.latitude, longitude: locationCoordinates.longitude)

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

Answer 1 · 2015-03-02T21:08:48Z

March 2, 2015 9:08pm

I don't see the startUpdatingLocation() method in your code so maybe that's the problem. I think you need to call this method on the location manager to start searching for the location. And then in the reverse Geocode you need to pass in the location of that same manager as well.

This is from my app and it worked fine.

let geoCoder = CLGeocoder()
var placemark: AnyObject
var error: NSError
geoCoder.reverseGeocodeLocation(manager.location, completionHandler: { (placemark, error) -> Void in
    if error != nil {
    println("Error: \(error.localizedDescription)")
        return
    }
    if placemark.count > 0 {
        let pm = placemark[0] as CLPlacemark
        self.locationLabel.text = "\(pm.locality), \(pm.country)"
    } else {
        println("Error with data")
    }
})

Answer 2 · 2015-03-04T14:56:05Z

March 4, 2015 2:56pm

Could it be that I just forgot to declare my placemark variable ? In any case your solution works, thanks!

Answer 3 · 2015-12-30T22:06:36Z

December 30, 2015 10:06pm

Antoine did you figure it out? this question is a bit old.

I'm pretty sure the answer is in the frist line using .NotDetermined Enum value, that is always the initial state of the app, you don't need to add this option, if the app is in .NotDetermined status it will prompt the user for authorization, but by you adding this clause here, you are not allowing it to get to the request part of your app and it is going straight into Alcatraz. Another thing to consider (not the reason your code is not rendering the results you expect, but for a cleaner code) You are declaring an instance of Geocoder , but then you use the class itself instead, you might want to check that as well.

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Antoine Guenet

Antoine Guenet

Reverse Geocoding with Swift (weather app)

3 Answers

Enara L. Otaegi

Enara L. Otaegi

Antoine Guenet

Antoine Guenet

Vinny Harris-Riviello

Vinny Harris-Riviello