Get the address of current user location

Question

I follow some tutorial and mix my awful code. Now I can get my current location. And when I tap on a button it will trigger a pin which locates on my current location. If I tap on the pin, the message shows address of my current.

I have two question:

1. Why I can not get a more precise address? Now I receive address with country, city and district, but without name of the road.

2. How can I get the "text" of the address of current location? I want to display the address in a UILabel elsewhere but don't know how to do that.

Thank you very much!

here's the .h

#import <UIKit/UIKit.h>
#import "MapKit/MapKit.h"
#import "CoreLocation/CoreLocation.h"

@interface UserLocationAddressViewController : UIViewController     <MKMapViewDelegate,MKReverseGeocoderDelegate>
{
    MKMapView *userLocationAddMapView;
    CLLocationManager *locationManager;
}

@property (nonatomic, retain) MKMapView *userLocationAddMapView;

-(IBAction)getUserLocationAddress:(id)sender;

@end

And Here's .m

#import "UserLocationAddressViewController.h"

@implementation UserLocationAddressViewController

@synthesize userLocationAddMapView;

-(IBAction)getUserLocationAddress:(id)sender
{
    MKReverseGeocoder *geoCoder = [[MKReverseGeocoder alloc] initWithCoordinate:locationManager.location.coordinate];
    geoCoder.delegate = self;
    [geoCoder start]; 
}

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

-(void)dealloc
{
    [userLocationAddMapView release];
    [super dealloc];
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];

self.userLocationAddMapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, 320, 460)];
    userLocationAddMapView.showsUserLocation = YES;
    userLocationAddMapView.delegate = self;
    self.userLocationAddMapView.mapType = MKMapTypeStandard;

    locationManager = [[CLLocationManager alloc] init];
    [locationManager startUpdatingLocation];
    CLLocationCoordinate2D coordinate = locationManager.location.coordinate;

    MKCoordinateRegion mapRegion;
    mapRegion.center = coordinate;
    MKCoordinateSpan mapSpan;
    mapSpan.latitudeDelta = 0.006;
    mapSpan.longitudeDelta = 0.006;
    mapRegion.span = mapSpan;
    [userLocationAddMapView setRegion:mapRegion animated:YES];
    self.userLocationAddMapView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    [self.view addSubview:self.userLocationAddMapView];

    self.navigationItem.rightBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle:@"Get Add" style:UIBarButtonItemStylePlain target:self action:@selector(getUserLocationAddress:)] autorelease];  
}

-(void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark
{
    NSLog(@"placemark %f %f", placemark.coordinate.latitude, placemark.coordinate.longitude);
    NSLog(@"addressDictionary %@", placemark.addressDictionary);
    [userLocationAddMapView addAnnotations:[NSArray arrayWithObjects:placemark, nil]];
    [geocoder release];
}

-(void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error
{
    NSLog(@"reverseGeocoder fail");
    [geocoder release];
}

- (void)viewDidUnload
{
    [super viewDidUnload];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

@end

Answer 1

Just place this delegate methods, I hope this may help you.

-- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error {
    NSLog(@"MKReverseGeocoder has failed.");

}

-- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark {
    currentLocation = [placemark.locality stringByAppendingFormat:@", "];
    currentLocation = [currentLocation stringByAppendingString:placemark.country];
    [indicator stopAnimating];
    txtLocation.text = currentLocation;

}

Answer 2

I have got the same issue, MKReverseGeocoder doesn't always return the full address, beacause sometimes the coordinates is not accurate enough and the service can't generate an approximative address. In order to get best results i have implemented an other reverse geocoding against yahoo. So basically if MKReverseGeocoder (google) doesn't return a full address, i query yahoo who can generate an approximative one.

On the other hand be carreful with MKReverseGeocoder it has been deprecated in IOS 5, they recommand to use CLGeocoder instead

Answer 3

You shouldn't really use MKReverseGeocoder as it has been depreciated by apple in iOS5, you should really use CLGeocoder. The following example will return a whole tonne of information which is based in the NSArray *placemarks, you can then iterate through them and call the keys in the assoc array.

#import "MapPoint.h"

@implementation MapPoint
@synthesize coordinate, title, dateAdded, subtitle, city, reverseGeo;

-(id)initWithCoordinates:(CLLocationCoordinate2D)c 
                   title:(NSString *)t {

    self = [super init];
    if (self) {

        coordinate = c;
        [self setTitle: t];
        [self setCurrentCity: [[CLLocation alloc] initWithLatitude:c.latitude longitude:c.longitude]];

        [self setDateAdded: [[NSDate alloc] init]];

    }
    return self;

}

-(void)setCurrentCity: (CLLocation *)loc {

    if (!self.reverseGeo) {
        self.reverseGeo = [[CLGeocoder alloc] init];
    }

    [self.reverseGeo reverseGeocodeLocation: loc completionHandler: 
     ^(NSArray *placemarks, NSError *error) {

         for (CLPlacemark *placemark in placemarks) {

             NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
             [formatter setTimeStyle:NSDateFormatterNoStyle];
             [formatter setDateStyle:NSDateFormatterLongStyle];

             NSString *dateString = [formatter stringFromDate: [self dateAdded]];
             [self setSubtitle: [dateString stringByAppendingString: [placemark locality] ] ];             

         }
     }];
}

@end