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iphone - Get location name from Latitude & Longitude in iOS

I want to find current location name from latitude and longitude,

Here is my code snippet I tried but my log shows null value in all the places except in placemark, placemark.ISOcountryCode and placemark.country

I want value of placemark.locality and placemark.subLocality but it is showing null values.

- (void)viewWillAppear:(BOOL)animated
{
     [super viewWillAppear:animated];

    // this creates the CCLocationManager that will find your current location
    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;
    [locationManager startUpdatingLocation];

}

// this delegate is called when the app successfully finds your current location
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    CLGeocoder *geocoder = [[CLGeocoder alloc] init];
    [geocoder reverseGeocodeLocation:locationManager.location
                   completionHandler:^(NSArray *placemarks, NSError *error) {
                       NSLog(@"reverseGeocodeLocation:completionHandler: Completion Handler called!");

                       if (error){
                           NSLog(@"Geocode failed with error: %@", error);
                           return;

                       }

                       NSLog(@"placemarks=%@",[placemarks objectAtIndex:0]);
                       CLPlacemark *placemark = [placemarks objectAtIndex:0];

                       NSLog(@"placemark.ISOcountryCode =%@",placemark.ISOcountryCode);
                       NSLog(@"placemark.country =%@",placemark.country);
                       NSLog(@"placemark.postalCode =%@",placemark.postalCode);
                       NSLog(@"placemark.administrativeArea =%@",placemark.administrativeArea);
                       NSLog(@"placemark.locality =%@",placemark.locality);
                       NSLog(@"placemark.subLocality =%@",placemark.subLocality);
                       NSLog(@"placemark.subThoroughfare =%@",placemark.subThoroughfare);

                   }];
}

// this delegate method is called if an error occurs in locating your current location
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
    NSLog(@"locationManager:%@ didFailWithError:%@", manager, error);
}

Thanks In Advance.

EDIT:

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    CLGeocoder *geocoder = [[CLGeocoder alloc] init];

    CLLocation *currentLocation = newLocation;

    if (currentLocation != nil)
        NSLog(@"longitude = %.8f
latitude = %.8f", currentLocation.coordinate.longitude,currentLocation.coordinate.latitude);

    // stop updating location in order to save battery power
    [locationManager stopUpdatingLocation];


    [geocoder reverseGeocodeLocation:currentLocation completionHandler:^(NSArray *placemarks, NSError *error)
     {
         NSLog(@"Found placemarks: %@, error: %@", placemarks, error);
         if (error == nil && [placemarks count] > 0)
         {
             CLPlacemark *placemark = [placemarks lastObject];

             // strAdd -> take bydefault value nil
             NSString *strAdd = nil;

             if ([placemark.subThoroughfare length] != 0)
                 strAdd = placemark.subThoroughfare;

             if ([placemark.thoroughfare length] != 0)
             {
                 // strAdd -> store value of current location
                 if ([strAdd length] != 0)
                     strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark thoroughfare]];
                 else
                 {
                     // strAdd -> store only this value,which is not null
                     strAdd = placemark.thoroughfare;
                 }
             }

             if ([placemark.postalCode length] != 0)
             {
                 if ([strAdd length] != 0)
                     strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark postalCode]];
                 else
                     strAdd = placemark.postalCode;
             }

             if ([placemark.locality length] != 0)
             {
                 if ([strAdd length] != 0)
                     strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark locality]];
                 else
                     strAdd = placemark.locality;
             }

             if ([placemark.administrativeArea length] != 0)
             {
                 if ([strAdd length] != 0)
                     strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark administrativeArea]];
                 else
                     strAdd = placemark.administrativeArea;
             }

             if ([placemark.country length] != 0)
             {
                 if ([strAdd length] != 0)
                     strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark country]];
                 else
                     strAdd = placemark.country;
             }
         }
     }];
}
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1 Answer

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by (71.8m points)

I'm giving you snippet which I'm using for resolving address. I'm including comment also at neccessary place to understand the code for you. Besides that feel free to ask any question from snippet if you get fail to understand anything.

Write following snippet in didUpdateToLocation method

NSLog(@"didUpdateToLocation: %@", newLocation);
CLLocation *currentLocation = newLocation;

if (currentLocation != nil)
    NSLog(@"longitude = %.8f
latitude = %.8f", currentLocation.coordinate.longitude,currentLocation.coordinate.latitude);

// stop updating location in order to save battery power
[locationManager stopUpdatingLocation];


// Reverse Geocoding
NSLog(@"Resolving the Address");

// “reverseGeocodeLocation” method to translate the locate data into a human-readable address.

// The reason for using "completionHandler" ----
   //  Instead of using delegate to provide feedback, the CLGeocoder uses “block” to deal with the response. By using block, you do not need to write a separate method. Just provide the code inline to execute after the geocoding call completes.

[geocoder reverseGeocodeLocation:currentLocation completionHandler:^(NSArray *placemarks, NSError *error)
 {
    NSLog(@"Found placemarks: %@, error: %@", placemarks, error);
    if (error == nil && [placemarks count] > 0)
    {
        placemark = [placemarks lastObject];

        // strAdd -> take bydefault value nil
        NSString *strAdd = nil;

        if ([placemark.subThoroughfare length] != 0)
            strAdd = placemark.subThoroughfare;

        if ([placemark.thoroughfare length] != 0)
        {
            // strAdd -> store value of current location
            if ([strAdd length] != 0)
                strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark thoroughfare]];
            else
            {
            // strAdd -> store only this value,which is not null
                strAdd = placemark.thoroughfare;
            }
        }

        if ([placemark.postalCode length] != 0)
        {
            if ([strAdd length] != 0)
                strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark postalCode]];
            else
                strAdd = placemark.postalCode;
        }

        if ([placemark.locality length] != 0)
        {
            if ([strAdd length] != 0)
                strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark locality]];
            else
                strAdd = placemark.locality;
        }

        if ([placemark.administrativeArea length] != 0)
        {
            if ([strAdd length] != 0)
                strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark administrativeArea]];
            else
                strAdd = placemark.administrativeArea;
        }

        if ([placemark.country length] != 0)
        {
            if ([strAdd length] != 0)
                strAdd = [NSString stringWithFormat:@"%@, %@",strAdd,[placemark country]];
            else
                strAdd = placemark.country;
        }

Where strAdd will return address using geolocation..

Enjoy Programming !!


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