objective-c - didUpdateToLocation 停止调用

Question

下面的方法

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation; 

调用 1 或 2 次，然后就不再调用了...为什么？

 -(void) startLocation {
 if (locationManager == nil)
    locationManager = [[CLLocationManager alloc] init];

locationManager.delegate = self;
locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;
locationManager.distanceFilter = 10;

[locationManager startUpdatingLocation];
  }

和:

       - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
contadorSegundos++;
float diferencaLatitude = 0;
float diferencaLongitude = 0;
NSLog(@"old latitude: %f", oldLocation.coordinate.latitude);
NSLog(@"old longitude: %f", oldLocation.coordinate.longitude);


NSLog(@"new longitude: %f", newLocation.coordinate.longitude);
NSLog(@"old latitude: %f", newLocation.coordinate.latitude);

if(oldLocation) {
if(oldLocation.coordinate.latitude > newLocation.coordinate.latitude)
    diferencaLatitude = oldLocation.coordinate.latitude - newLocation.coordinate.latitude;
else if(newLocation.coordinate.latitude > oldLocation.coordinate.latitude)
    diferencaLatitude = newLocation.coordinate.latitude - oldLocation.coordinate.latitude;
}

if (oldLocation) {

if(oldLocation.coordinate.longitude > newLocation.coordinate.longitude)
    diferencaLongitude = oldLocation.coordinate.longitude - newLocation.coordinate.longitude;
else if(newLocation.coordinate.longitude > oldLocation.coordinate.longitude)
    diferencaLongitude = newLocation.coordinate.longitude - oldLocation.coordinate.longitude;
}

//NSLog(@"dif lat %f", diferencaLatitude);

//NSLog(@"dif long %f", differencaLongitude);

CLLocationCoordinate2D coord;
if ((diferencaLatitude > 1) || (diferencaLongitude > 1)) {
    _emMovimento = YES;
    NSLog(@"em movimento");
}
else {
    if(contadorSegundos > 10) {
    _emMovimento = NO;
    contadorSegundos = 0;
        NSLog(@"parado");
    }
}

coord.longitude = newLocation.coordinate.longitude;
coord.latitude = newLocation.coordinate.latitude;
_latitude = coord.latitude;
_longitude = coord.longitude;

NSLog(@"latitude: %f", _latitude);
NSLog(@"longitude: %f", _longitude);
MKReverseGeocoder *geocoder = [[MKReverseGeocoder alloc] initWithCoordinate:coord];
[geocoder setDelegate:self];
[geocoder start];

Answer 1

这个问题是因为ARC自动释放了LocationManager对象。