Why dosen't CLLocationManager startUpdatingLocation fire in iOS8?

Question

I'm an test an existing locations functionality in iOS 8.0 using the simulators that come with XCode 6. I am unable to get CLLocationManager.startUpdatingLocation to trigger either CLLocationManagerDelegate.locationManager:didUpdateLocations or CLLocationManagerDelegate.locationManager:didFailWithError.

I don't get the ""My App" Would Like to Use Your Current Location" alert, like I do on the iOS 7.0.3 simulators. I have used the Maps app to verify that the simulated locations set.

This works fine in the iOS 7.0.3 simulators.

Where I'm I going wrong?

Answer 1

iOS 8 requires that you call either CLLocationManager.requestWhenInUseAuthorization or CLLocationManager.requestAlwaysAuthorization before you call CLLocationManager.startUpdatingLocation.

@interface MyViewController : UIViewController <CLLocationManagerDelegate>

@property CLLocationManager *locationManager;

@end

requestWhenInUseAuthorization and requestAlwaysAuthorization run asynchronously so you want to make sure that your CLLocationManager object isn't cleaned-up before the use can respond to the alert.

- (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 {
    ...
}

When you implement CLLocationManagerDelegate you now need to implement the locationManager:didChangeAuthorizationStatus: method as well. Within this method you can check if the user has given the app permission or not, and act accordingly.

If [CLLocationManager authorizationStatus] = nil then locationManager:didChangeAuthorizationStatus: will be called when the authorizationStatus is set to kCLAuthorizationStatusNotDetermined and again when the user make their selection from the alert dialog.

Answer 2

...Also to add to Adrian Toman's answer

Do not forget to add NSLocationWhenInUseUsageDescription or NSLocationAlwaysUsageDescription to you application-Info.plist file.

Once you add the property to your plist, you also need to add a string value to it, this string value will be presented to the user when you are asking for their permission to use their location.

Answer 3

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

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


}

And Add following in Info.plist

Answer 4

In addition to Adrian Toman's answer if the device is WiFi only try to disable/enable location settings.

Answer 5

I once encountered this problem, when I called startUpdatingLocation, locationManager:(CLLocationManager *)manager didUpdateLocations: did not get response. Even if I followed all instruction which others provided here, I couldn't get this method triggered.

Finally I realized one thing critical to it was it needed set the delegate of the locationManager to "self" (where you implemented the method locationManager:(CLLocationManager *)manager didUpdateLocations:).

Eventually, everything ran well after that.