我的应用在iOS 7上运行良好,但在iOS 8 SDK上却无法运行。

CLLocationManager不返回位置,我没有看到我的应用程序下设置->位置服务。我在这个问题上做了谷歌搜索,但没有任何结果。会有什么问题呢?


当前回答

我的解决方案可以在Xcode 5中编译:

#ifdef __IPHONE_8_0
    NSUInteger code = [CLLocationManager authorizationStatus];
    if (code == kCLAuthorizationStatusNotDetermined && ([self.locationManager respondsToSelector:@selector(requestAlwaysAuthorization)] || [self.locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)])) {
        // choose one request according to your business.
        if([[NSBundle mainBundle] objectForInfoDictionaryKey:@"NSLocationAlwaysUsageDescription"]){
            [self.locationManager requestAlwaysAuthorization];
        } else if([[NSBundle mainBundle] objectForInfoDictionaryKey:@"NSLocationWhenInUseUsageDescription"]) {
            [self.locationManager  requestWhenInUseAuthorization];
        } else {
            NSLog(@"Info.plist does not contain NSLocationAlwaysUsageDescription or NSLocationWhenInUseUsageDescription");
        }
    }
#endif
    [self.locationManager startUpdatingLocation];

其他回答

        // ** Don't forget to add NSLocationWhenInUseUsageDescription in MyApp-Info.plist and give it a string

        self.locationManager = [[CLLocationManager alloc] init];
        self.locationManager.delegate = self;
        // Check for iOS 8. Without this guard the code will crash with "unknown selector" on iOS 7.
        if ([self.locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
            [self.locationManager requestWhenInUseAuthorization];
        }
        [self.locationManager startUpdatingLocation];


    // Location Manager Delegate Methods    
    - (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
    {
        NSLog(@"%@", [locations lastObject]);

}

我在iOS9中得到了类似的错误(使用Xcode 7和Swift 2): 试图启动MapKit位置更新而没有提示位置授权。必须先调用-[CLLocationManager requestWhenInUseAuthorization]或-[CLLocationManager requestAlwaysAuthorization]。 我是跟着一个教程,但导师使用的是iOS8和Swift 1.2。在Xcode 7和Swift 2中有一些变化,我发现了这段代码,它对我来说很好(如果有人需要帮助):

import UIKit
import MapKit
import CoreLocation

class MapViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate {

    // MARK: Properties
    @IBOutlet weak var mapView: MKMapView!

    let locationManager = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()

        self.locationManager.delegate = self
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
        self.locationManager.requestWhenInUseAuthorization()
        self.locationManager.startUpdatingLocation()
        self.mapView.showsUserLocation = true

    }

    // MARK: - Location Delegate Methods

    func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        let location = locations.last
        let center = CLLocationCoordinate2D(latitude: location!.coordinate.latitude, longitude: location!.coordinate.longitude)
        let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 1, longitudeDelta: 1))
        self.mapView.setRegion(region, animated: true)
    }

    func locationManager(manager: CLLocationManager, didFailWithError error: NSError) {
        print("Errors: " + error.localizedDescription)
    }
}

最后,我把它放到info.plist中: 信息属性列表:NSLocationWhenInUseUsageDescription 取值范围:应用需要为员工提供位置服务器

解决方案与向后兼容,不产生Xcode警告:

SEL requestSelector = NSSelectorFromString(@"requestWhenInUseAuthorization");
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined &&
  [self.locationManager respondsToSelector:requestSelector]) {
((void (*)(id, SEL))[self.locationManager methodForSelector:requestSelector])(self.locationManager, requestSelector);
  [self.locationManager startUpdatingLocation];
} else {
  [self.locationManager startUpdatingLocation];
}

在Info.plist中设置NSLocationWhenInUseUsageDescription键。

对于iOS版本11.0+: 在Info.plist中设置NSLocationAlwaysAndWhenInUseUsageDescription键。还有另外2把钥匙。

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];
    }
}

为了访问用户在iOS中的位置。您需要添加两个键

NSLocationWhenInUseUsageDescription

NSLocationAlwaysUsageDescription

进入信息。plist文件。

    <key>NSLocationWhenInUseUsageDescription</key>
    <string>Because I want to know where you are!</string>
    <key>NSLocationAlwaysUsageDescription</key>
    <string>Want to know where you are!</string>

请看下图。