iOS8何时分配初始化CLLocationManager来调用requestWhenInUseAuthorization？

Question

当我尝试在其getter内分配初始化我的CLLocationManager时，我没有收到针对位置自动化的弹出请求。 但是，当我放入viewDidLoad时，它确实可以工作。

我的代码看起来像这样：

- (void)viewDidLoad {
    [super viewDidLoad];
    self.mapView.delegate = self;
    self.locationManager = [[CLLocationManager alloc] init]; //when i put this here it works
    self.locationManager.delegate = self;
    CLAuthorizationStatus status = [CLLocationManager authorizationStatus];
    if(![CLLocationManager authorizationStatus])
    {
        [self.locationManager requestWhenInUseAuthorization];
    }
    self.mapView.showsUserLocation = YES;
    [self.mapView setMapType:MKMapTypeStandard];
    [self.mapView setZoomEnabled:YES];
    [self.mapView setScrollEnabled:YES];
}

但是当我像这样进行分配初始化时，它不起作用：

-(CLLocationManager *)locationManager
{
    if(_locationManager) _locationManager = [[CLLocationManager alloc]init];
    return _locationManager;
}

谁能向我解释为什么？

Answer 1

由于访问器方法中存在逻辑错误，因此：

- (CLLocationManager *)locationManager
{
    if(_locationManager == nil) _locationManager = [[CLLocationManager alloc] init];
    return _locationManager;
}