向后兼容解决方案:

SEL requestSelector = NSSelectorFromString(@"requestWhenInUseAuthorization");
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined &&
    [self.locationManager respondsToSelector:requestSelector]) {
    [self.locationManager performSelector:requestSelector withObject:NULL];
} else {
    [self.locationManager startUpdatingLocation];
}

在Info.plist中设置NSLocationWhenInUseUsageDescription键

用于询问位置的旧代码将无法在iOS 8中使用。您可以尝试使用此方法进行位置授权:

- (void)requestAlwaysAuthorization
{
    CLAuthorizationStatus status = [CLLocationManager authorizationStatus];

    // If the status is denied or only granted for when in use, display an alert
    if (status == kCLAuthorizationStatusAuthorizedWhenInUse || status ==        kCLAuthorizationStatusDenied) {
        NSString *title;
        title = (status == kCLAuthorizationStatusDenied) ? @"Location services are off" :   @"Background location is not enabled";
        NSString *message = @"To use background location you must turn on 'Always' in the Location Services Settings";

        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
                                                            message:message
                                                           delegate:self
                                                  cancelButtonTitle:@"Cancel"
                                                  otherButtonTitles:@"Settings", nil];
        [alertView show];
    }
    // The user has not enabled any location services. Request background authorization.
    else if (status == kCLAuthorizationStatusNotDetermined) {
        [self.locationManager requestAlwaysAuthorization];
    }
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if (buttonIndex == 1) {
        // Send the user to the Settings for this app
        NSURL *settingsURL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
        [[UIApplication sharedApplication] openURL:settingsURL];
    }
}

- (void)startLocationManager
{
    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    locationManager.distanceFilter = kCLDistanceFilterNone; //whenever we move
    locationManager.desiredAccuracy = kCLLocationAccuracyBest;

    [locationManager startUpdatingLocation];
    [locationManager requestWhenInUseAuthorization]; // Add This Line


}

还有你的信息。plist文件

在[locationManager startUpdatingLocation];之前，添加一个iOS8位置服务请求:

if([locationManager respondsToSelector:@selector(requestAlwaysAuthorization)])
    [locationManager requestAlwaysAuthorization];

编辑应用程序的信息。并添加键NSLocationAlwaysUsageDescription与字符串值，将显示给用户(例如，我们尽我们最大的努力来保持您的电池寿命。)

如果你的应用程序只在应用程序打开时需要位置服务，请替换:

requestAlwaysAuthorization with requestWhenInUseAuthorization和

NSLocationAlwaysUsageDescription和NSLocationWhenInUseUsageDescription。

为了确保这与iOS 7向后兼容，你应该检查用户运行的是iOS 8还是iOS 7。例如:

#define IS_OS_8_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)

//In ViewDidLoad
if(IS_OS_8_OR_LATER) {
   [self.locationManager requestAlwaysAuthorization];
}

[self.locationManager startUpdatingLocation];

Swift开发者常犯的一个错误:

首先确保你添加了一个值到plist为NSLocationWhenInUseUsageDescription或NSLocationAlwaysUsageDescription。

如果你仍然没有看到一个窗口弹出要求授权，看看你是否把行var locationManager = CLLocationManager()在你的视图控制器的viewDidLoad方法。如果这样做，那么即使调用locationManager.requestWhenInUseAuthorization()，也不会显示任何内容。这是因为在viewDidLoad执行后，locationManager变量被释放(清除)。

解决方案是在类方法的顶部找到var locationManager = CLLocationManager()行。