位置管理器給出空座標

Question

以下代碼導致空座標。奇怪的是UIAlert提示應用程序在用戶可以選擇「是」之前使用當前位置。

我的代碼，我已經使用：

CLLocationManager *locationManager; 
locationManager.desiredAccuracy = kCLLocationAccuracyBest; 
[locationManager startUpdatingLocation]; 
locationManager = [[CLLocationManager alloc] init]; 
locationManager.distanceFilter = kCLDistanceFilterNone; 
locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters; 
[locationManager startUpdatingLocation]; 
float latitude = locationManager.location.coordinate.latitude; 
float longitude = locationManager.location.coordinate.longitude; 
NSLog(@"%.8f",latitude); 
NSLog(@"%.8f",longitude); 

的NSLog的打印0.0000000兩個座標。

謝謝！

Answer 1

你得到0的原因是因爲外景經理並沒有在這一點（它已經開始思考）

你需要設置你的類作爲外景經理的代表收集的任何數據（即提供每當檢索到新位置時調用的函數），並保留您的位置管理器。

// Inside .m file 

@interface MyClass() <CLLocationManagerDelegate> // Declare this class to implement protocol CLLocationManagerDelegate 

@property (strong, nonatomic) CLLocationManager* locationManager; // Retains it with strong keyword 

@end 

@implementation MyClass 

// Inside some method 

    self.locationManager = [[CLLocationManager alloc] init]; 
    self.locationManager.delegate = self; 
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest; 
    self.locationManager.distanceFilter = kCLDistanceFilterNone; 
    [self.locationManager startUpdatingLocation]; 

// Delegate method 
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations { 
    CLLocation* loc = [locations lastObject]; // locations is guaranteed to have at least one object 
    float latitude = loc.coordinate.latitude; 
    float longitude = loc.coordinate.longitude; 
    NSLog(@"%.8f",latitude); 
    NSLog(@"%.8f",longitude); 
}