ios8 - 为什么 CLLocationManager startUpdatingLocation 在 iOS8 中不触发？

Question

我正在使用 XCode 6 附带的模拟器测试 iOS 8.0 中的现有位置功能。我无法获得 CLLocationManager.startUpdatingLocation触发 CLLocationManagerDelegate.locationManager:didUpdateLocations或者
CLLocationManagerDelegate.locationManager:didFailWithError .

我没有像在 iOS 7.0.3 模拟器上那样收到“我的应用程序”想要使用您当前位置的警报。我使用 map 应用程序来验证模拟位置设置。

这在 iOS 7.0.3 模拟器中运行良好。

我哪里错了？

Answer 1

iOS 8 要求您调用 CLLocationManager.requestWhenInUseAuthorization或 CLLocationManager.requestAlwaysAuthorization在您调用之前 CLLocationManager.startUpdatingLocation .

@interface MyViewController : UIViewController <CLLocationManagerDelegate>

@property CLLocationManager *locationManager;

@end

requestWhenInUseAuthorization和 requestAlwaysAuthorization异步运行，因此您要确保您的 CLLocationManager 对象在用户可以响应警报之前未被清除。

- (void) viewDidAppear:(BOOL)animated {
    if ([CLLocationManager locationServicesEnabled]) {
        self.locationManager = [CLLocationManager new];
        self.locationManager.delegate = self;
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;

        SEL selector = NSSelectorFromString(@"requestWhenInUseAuthorization");
        if ([self.locationManager respondsToSelector:selector]) {
            [self.locationManager requestWhenInUseAuthorization];
        } else {
            [self.locationManager startUpdatingLocation];
        }
    } else {
        ...
    }
}

- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status {
    if (status == kCLAuthorizationStatusAuthorizedWhenInUse) {
        [self.locationManager startUpdatingLocation];
    } else if (status == kCLAuthorizationStatusAuthorized) {
        // iOS 7 will redundantly call this line.
        [self.locationManager startUpdatingLocation];
    } else if (status > kCLAuthorizationStatusNotDetermined) {
        ...
    }
}

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

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
    ...
}

当您实现 CLLocationManagerDelegate您现在需要实现 locationManager:didChangeAuthorizationStatus:方法也一样。在此方法中，您可以检查用户是否已授予应用程序权限，并采取相应措施。

如 [CLLocationManager authorizationStatus] = nil 然后 locationManager:didChangeAuthorizationStatus: 当authorizationStatus 设置为 时将被调用 kCLAuthorizationStatusNotDetermined 当用户从警报对话框中进行选择时再次出现。