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

对我来说,问题是CLLocationManagerDelegate类是私有的,这阻止了所有的委托方法被调用。我想这不是很常见的情况,但我想我应该提到它,以防它能帮助到任何人。

其他回答

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];

对于那些使用Xamarin,我必须添加关键NSLocationWhenInUseUsageDescription的信息。手动plist,因为在Xamarin 5.5.3 Build 6或XCode 6.1的下拉列表中都不可用-只有NSLocationUsageDescription在列表中,这导致CLLocationManager继续无声地失败。

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。

        // ** 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]);

}

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];
    }
}