问未在计时器Objective-C上调用委托

EN

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//Updating Location
[Location sharedLocation];

//Timer for reloading the XML
recheckTimer = [NSTimer scheduledTimerWithTimeInterval:30 target:self selector:@selector(recheckLocation) userInfo:nil repeats:YES];
return YES:
}

-(void)recheckLocation
{
  //Updating Location
  [Location sharedLocation];
  NSLog(@"Timer Triggered");
}

#import "Location.h"

@implementation Location


@synthesize locationManager;


- (id)init {
  self = [super init];

  if(self) {
    self.locationManager = [CLLocationManager new];
    [self.locationManager setDelegate:self];
    [self.locationManager setDistanceFilter:500];//Metres
    [self.locationManager setHeadingFilter:90];
    [self.locationManager startMonitoringSignificantLocationChanges];
  }
  return self;
}


+ (Location*)sharedLocation {
  static Location* sharedLocation;
  if(!sharedLocation) {
    @synchronized(sharedLocation) {
      sharedLocation = [Location new];
    }
  }

  return sharedLocation;
}


//LOCATION CODING
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSLog(@"didFailWithError' %@", error);
UIAlertView *errorAlert = [[UIAlertView alloc]initWithTitle:@"Error" message:@"Failed to Get Your Current 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) {

    //Resolve Web Address
    webAddressResolved = [NSString stringWithFormat:@"XZYYFASDFA%f,%f.xml", currentLocation.coordinate.latitude, currentLocation.coordinate.longitude];
    NSLog(@"Address Resolved %@", webAddressResolved);
  }

  //Stop Location Manager
  [locationManager stopMonitoringSignificantLocationChanges];

}