Location service improve the app by enhancing user experience. Lots of application's features base on location service like finding near places, restaurant and whatever user want to search. Uber, Ola, Nearby and tons of applications are based on location service and display required content on the basis of that. Suppose we are stand on a place and want to search restaurant near current location, in this case we must know user current location and than can display result according to user search.
Now question is how can we get user current location? It is not a difficult task, every language provide in build framework and library for perform this task.
Apple provide Core Location Framework for obtaining all necessary information regarding user's current location. Core Location Framework provide geographic location of device.
Click here to know about Geographic coordinate system.
Lets start the coding stuff to fetch current location of a user.
Add Core Location Framework in the build phase of target under"Link Binary with Library" section, switch to controller class and import location framework and implement
<CLLocationManagerDelegate> and declare an instance of
CLLocationManager.
#import <CoreLocation/CoreLocation.h>
@interface HomeMapViewController : UIViewController<CLLocationManagerDelegate>{
CLLocationManager *locationManager;
}
@end
Now switch to .m class and add method for fetch current location
@implementation HomeMapViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
[self getCurrentLocation];
}
-(void) getCurrentLocation{
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
if ([locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
[locationManager requestWhenInUseAuthorization];
}
[locationManager startUpdatingLocation];
}
// define delegate methods of <CLLocationManagerDelegate>
- (void)locationManager:(CLLocationManager *)manager
didFailWithError:(NSError *)error{
NSLog(@"Error to fetch location = %@", error);
}
-(void) locationManager:(CLLocationManager *)manager didUpdateLocations: (NSArray<CLLocation *> *)locations{
CLLocation *location = [locations lastObject];
CLLocationCoordinate2D cord = location.coordinate;
NSLog(@"Current Location\n Latitude - %f \n Longitude - %f", cord.latitude, cord.longitude);
}@end
Now run the app and allow the application to fetch your current location.
You can see latitude and longitude value of location on console area. We are successfully getting current location of device/user.
We can stop location update service any time by using 'stopUpdatingLocation' method. It will be better to stop location service after getting current location. add following line of code inside of
'didUpdateLocations' method
[locationManager stopUpdatingLocation];
But the problem is, value of location in form of latitude and longitude and it is not in human readable address. Lets convert the coordinate value in human readable address.
CLGeocoder class provide service for convert coordinate to human readable address. By specify the latitude and longitude of a given location, you can use CLGeocoder to find a user-readable address.
Lets create a new method for getting human readable address of coordinate.
-(void) getReadableAddressFrom:(CLLocation *)location{
CLGeocoder *geocoder = [[CLGeocoder alloc] init];
[geocoder reverseGeocodeLocation:location completionHandler:^(NSArray *placemarks, NSError *error) {
NSLog(@"Found placemarks: %@, error: %@", placemarks, error);
if (error == nil && [placemarks count] > 0) {
CLPlacemark *placemark = [placemarks lastObject];
NSString *address = [NSString stringWithFormat:@"%@ %@\n%@ %@\n%@\n%@",placemark.subThoroughfare, placemark.thoroughfare,placemark.postalCode, placemark.locality,placemark.administrativeArea,placemark.country];
NSLog(@"Address = %@", address);
} else {
NSLog(@"%@", error.debugDescription);
}
} ];
}
Inside 'didUpdateLocations' method add line of code to call above method.
[self getReadableAddressFrom:location];
Run the code and check the console, you can see address details.
Note : For running the application on simulator set the default address of simulator.
In the menu bar, select “Debug” -> “Location” for setting the simulator location.
