iphone - 从iOS中的经度和纬度获取位置名称

我想从经度和纬度中找到当前的位置名称，

这是我尝试过的代码段，但是我的日志在所有地方都显示了空值，除了placemark，placemark.ISOcountryCode和placemark.country之外

我想要placemark.locality和placemark.subLocality的值，但它显示的是空值。

- (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);
}

提前谢谢。

编辑:

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

    CLLocation *currentLocation = newLocation;

    if (currentLocation != nil)
        NSLog(@"longitude = %.8f\nlatitude = %.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;
             }
         }
     }];
}

最佳答案

我给你我用来解析地址的代码段。我还将在必要的地方添加注释，以帮助您理解代码。除此之外，如果您不了解任何内容，请随时向代码段提出任何问题。

在didUpdateToLocation方法中编写以下代码段

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

if (currentLocation != nil)
    NSLog(@"longitude = %.8f\nlatitude = %.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;
        }

其中strAdd将使用地理位置返回地址。

享受编程!