didUpdateToLocation调用多个

Question

我有一个iOS应用程序巫婆使用用户的当前位置.我这样做:

-(void)startGeoloc{

    NSLog(@"start geoloc");

    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    locationManager.desiredAccuracy=kCLLocationAccuracyHundredMeters;
    [locationManager startUpdatingLocation];
}

#pragma mark - CLLocationManagerDelegate methods
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    [locationManager stopUpdatingLocation];
    AppDelegate *apDelegate =(AppDelegate *)[UIApplication sharedApplication].delegate;
    apDelegate.modeGeoloc = YES;
    [self callWebService:locationManager.location];

}

问题是,我的方法callWebService:locationManager.location被调用两次,我只想称它为一次.我怎么能这样做？谢谢你的回答

Answer 1

要确保locationManager仅调用"didUpdate ..."方法一次,请使用BOOL来引用是否已找到该位置.

1. 创建ivar BOOL:

   @property BOOL didFindLocation;
   

2. 在locationManager startUpdatingLocation之前,将新BOOL设置为NO.这样您就可以随意调用新的位置更新.

   -(void) startFindingLocation {
   
       self.didFindLocation = NO; // like this
   
       locationManager = [[CLLocationManager alloc] init];
       [locationManager setDelegate:self]
       [locationManager setDesiredAccuracy:kCLLocationAccuracyHundredMeters];
       [locationManager startUpdatingLocation];
   }
   

3. 在"didUpdateLocations"中,检查它.

   - (void) locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations {
   
       if (!self.didFindLocation) {
           self.didFindLocation = YES;
           [locationManager stopUpdatingLocation];
   
           // do the rest of your stuff
   
       }
   }
   

如果可能,请不要在代码中的任何其他位置设置didFindLocation以避免混淆.