地理位置错误目标C.

Question

我正在尝试创建一个应用，它会在我在故事板中设置的标签中收集并显示我的经度和纬度值。如果我只是在我的IBAction实例中为我的标签分配一个简单的文本，它运行正常并显示文本。但是，当我在下面的IBAction实例中使用代码时，按下我的按钮时，我的标签中没有显示任何内容。

  @interface ViewController ()

@end

@implementation ViewController {
     CLLocationManager *locationManager;
}


@synthesize longitude, latitude;

- (void)viewDidLoad {
[super viewDidLoad];
locationManager = [[CLLocationManager alloc] init];

   }

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}

- (IBAction)getCurrentLocation:(id)sender {

  locationManager.delegate = self;
  locationManager.desiredAccuracy = kCLLocationAccuracyBest;
  [locationManager startUpdatingLocation];
  }

  - (void)locationManager:(CLLocationManager *)manager                        didFailWithError:(NSError *)error
{
NSLog(@"didFailWithError: %@", error);
UIAlertView *errorAlert = [[UIAlertView alloc]
                           initWithTitle:@"Error" message:@"Failed to    Get Your Location" delegate:nil cancelButtonTitle:@"OK"    otherButtonTitles:nil];
[errorAlert show];
}

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
NSLog(@"didUpdateToLocation: %@", newLocation);
CLLocation *currentLocation = newLocation;

if (currentLocation != nil) {
    longitude.text = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.longitude];
    latitude.text = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.latitude];
}
 }
@end