Question

I was trying to implement a separate class for managing my location. I wanted to get my location whenever I click a button.

gpsFilter.h

#import <Foundation/Foundation.h>
#import <CoreLocation/CoreLocation.h>

@interface gpsFilter : NSObject <CLLocationManagerDelegate>

@property (nonatomic, retain) CLLocationManager *gpsManager;
@property (nonatomic, retain) NSString * latitude;
@property (nonatomic, retain) NSString * longitude;
@end

gpsFilter.m.

#import "gpsFilter.h"

@implementation gpsFilter

- (id) init{
self = [super init];
if(self != nil){
    self.gpsManager = [[CLLocationManager alloc] init];
    self.gpsManager.delegate = self;
    [self.gpsManager startUpdatingLocation];
    BOOL enable = [CLLocationManager locationServicesEnabled];
    NSLog(@"%@", enable? @"Enabled" : @"Not Enabled");
}
return self;
}

- (void)gpsManager:(CLLocationManager *) manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
NSLog(@"didUpdateToLocation: %@", newLocation);
CLLocation *currentLocation = newLocation;
if(currentLocation != nil){
    self.latitude = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.longitude];
    self.longitude = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.latitude];
}
}

- (void)gpsManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSLog(@"didFailWithError: %@", error);
}
@end

I am using a separate class because I wanted to add smoothing filter in the future. I don’t get any updates. The NSLog is never triggered. I think some variable is getting autoreleased, but I am not sure, which one.

The viewController code is as follows.

#import "gpstestViewController.h"

@interface gpstestViewController (){

}

@end

@implementation gpstestViewController


- (void)viewDidLoad
 {
[super viewDidLoad];
self.location = [[gpsFilter alloc] init];
// Do any additional setup after loading the view, typically from a nib.
}


- (IBAction)getloca:(id)sender {
self.latitudeLabel.text = [self.location latitude];
self.longitudeLabel.text = [self.location longitude];

}

- (IBAction)getLocation:(id)sender {
self.latitudeLabel.text = [self.location latitude];
self.longitudeLabel.text = [self.location longitude];

}
@end

I am sorry that I am dumping a lot of code, but I am a newbie to ios programming and I am not able to find what the problem is.

EDIT: The updateLocation delegate method is not being called at all.

Answer 1

The delegate methods must be named locationManager:didUpdateToLocation:fromLocation: and locationManager:didFailWithError:.

You cannot use custom method names like gpsManager:didUpdateToLocation:fromLocation:.

Also note that locationManager:didUpdateToLocation:fromLocation: is deprecated as of iOS 6 and you should use locationManager:didUpdateLocations:.