在我的 iPod touch 上使用核心位置

Question

我一直在尝试在我的设备上实现以下代码：-

 #import <UIKit/UIKit.h>
 #import <CoreLocation/CoreLocation.h>
 @interface Whereami1ViewController : UIViewController<CLLocationManagerDelegate>
  {
      CLLocationManager *locationManager;

      __weak IBOutlet UILabel *coordLabel;
  }
 @end

 @implementation Whereami1ViewController

 - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
  {
        self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
        if (self) {
          // Custom initialization
             locationManager = [[CLLocationManager alloc] init];
              [locationManager setDelegate:self];

             [locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
             locationManager.distanceFilter= 5.00;//5 meters

             [locationManager startUpdatingLocation];


         }
         return self;
       }

       -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray  *)locations{//location manager sends this message to self
          NSLog(@"%@",NSStringFromSelector(_cmd));
           NSLog(@"new location–– %@",[locations lastObject]);
           NSLog(@"latitude= %f, longitude= %f",[[locations lastObject] coordinate].latitude, [[locations lastObject] coordinate].longitude);
          CGSize coordData= {[[locations lastObject] coordinate].latitude, [[locations lastObject] coordinate].longitude};

          coordLabel.text= NSStringFromCGSize(coordData);//setting the label's text

       }
       -(void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error{
           NSLog(@"%@",NSStringFromSelector(_cmd));
           NSLog(@"location not found: %@", error);
       }
       @end

在代码中，我将距离过滤器设置为 5 米。这意味着在设备移动 5 米后，它应该将标签的文本更新到新坐标(latitude, longitude)。但这在现实中并没有发生。我的意思是

-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray  *)locations

should get called only when the device has moved more than 5 meters.实际上，设备卡在初始数据上（视图中标签没有更新）..

我做错了什么..这不是正确的方法吗？？

Answer 1

iPod touch 使用 WiFi 网络进行定位服务。所以 5 米移动可能无法获得好位置或更新？！它的行为与同样使用 GPS 信号进行定位的 iPhone 或 iPda 完全不同。