ios - Xcode 6.2 beta 和 iOS 8 模拟器 : location manager authorization dialogue fails to appear: bug or failure to understand?

Question

我找到了以下 solution解释如何在 iOS 8 中使用定位服务。不幸的是，我只有一个 iPhone 6 模拟器而不是真正的设备。我尝试在 viewDidLoad 方法中添加此代码，但从未显示授权对话框。为什么是这样？

我在下面添加了一个断点，它被执行但不显示对话框..:

    // Will open an confirm dialog to get user's approval
    [locationManager requestAlwaysAuthorization];

这是完整的 viewDidLoad 方法:

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    // Initialize location manager
locationManager = [CLLocationManager new];
locationManager.delegate = self;

float system = [[[UIDevice currentDevice] systemVersion] floatValue ];

if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0 &&
    [CLLocationManager authorizationStatus] != kCLAuthorizationStatusAuthorizedAlways
    ) {
    // Will open an confirm dialog to get user's approval
    [locationManager requestAlwaysAuthorization];
} else {
    [locationManager startUpdatingLocation]; //Will update location immediately
}
locationManager.desiredAccuracy = kCLLocationAccuracyBest;

PS:我还修改了 info.plist 如下:



PPS:

这就是我(在同一个 ViewController 中)实现 其余部分的方式CLLocationManagerDelegate 协议(protocol) :

#pragma mark - CLLocationManagerDelegate
- (void)locationManager:(CLLocationManager*)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status
{
    switch (status) {
        case kCLAuthorizationStatusNotDetermined: {
            NSLog(@"User still thinking..");
        } break;
        case kCLAuthorizationStatusDenied: {
            NSLog(@"User dislikes your app");
        } break;
        case kCLAuthorizationStatusAuthorizedWhenInUse:
        case kCLAuthorizationStatusAuthorizedAlways: {
            [locationManager startUpdatingLocation];
        } break;
        default:
            break;
    }
}

- (void)locationManager:(CLLocationManager *)manager
     didUpdateLocations:(NSArray *)locations {
    CLLocation *location = [locations lastObject];
    NSLog(@"lat%f - lon%f", location.coordinate.latitude, location.coordinate.longitude);
}

编辑 2:我按照答案中的建议添加了以下代码块。代码已执行，但对话未能出现。

#pragma mark - CLLocationManagerDelegate
- (void)locationManager:(CLLocationManager*)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status
{
    switch (status) {
        case kCLAuthorizationStatusNotDetermined: {
            if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0){
                [locationManager requestAlwaysAuthorization];
            }
        } break;
        case kCLAuthorizationStatusDenied: {
            NSLog(@"User dislikes your app");
        } break;
        case kCLAuthorizationStatusAuthorizedWhenInUse:
        case kCLAuthorizationStatusAuthorizedAlways: {
            [locationManager startUpdatingLocation];
        } break;
        default:
            break;
    }
}

Answer 1

将此添加到 didChangeAuthorizationStatus:

case kCLAuthorizationStatusNotDetermined: {
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
        [locationManager requestAlwaysAuthorization];
    }

编辑

if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0 &&
    [CLLocationManager authorizationStatus] != kCLAuthorizationStatusAuthorizedAlways
    ) {
    // Will open an confirm dialog to get user's approval
        [locationManager requestAlwaysAuthorization];
    }

    [locationManager startUpdatingLocation]; //Will update location immediately