iOS 8 Map Kit Obj-C Cannot Get Users Location

Question

I am working with Map Kit in iOS 8 using Obj-C NOT SWIFT. I cannot get the device location it is set a 0.00, 0.00 and I am getting the error:

Trying to start MapKit location updates without prompting for location authorization. Must call -[CLLocationManager requestWhenInUseAuthorization] or -[CLLocationManager requestAlwaysAuthorization] first.

I have implemented: ( I have tried only one at a time and no luck )

if(IS_OS_8_OR_LATER) {
    [self.locationManager requestWhenInUseAuthorization];
    [self.locationManager requestAlwaysAuthorization];
}
[self.locationManager startUpdatingLocation]; 

And in info.plist

NSLocationWhenInUseUsageDescription  :   App would like to use your location.
NSLocationAlwaysUsageDescription  :  App would like to use your location.

I do get prompted to allow the app to use my location but after I agree nothing changes. The location is being showed as 0.00, 0.00.

Code for displaying users location:

//Get Location
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.distanceFilter = kCLDistanceFilterNone;
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[self.locationManager startUpdatingLocation];

MKCoordinateRegion region = { { 0.0, 0.0 }, { 0.0, 0.0 } };
region.center.latitude = self.locationManager.location.coordinate.latitude;
region.center.longitude = self.locationManager.location.coordinate.longitude;
region.span.longitudeDelta = 0.005f;
region.span.longitudeDelta = 0.005f;
[mapView setRegion:region animated:YES];

Mike.

**EDIT: View Answer Below.

Predella

I can't get cl to work right either. with this beta (that feels alpha) I don't think you're to blame if it works on ios7 – Domineer

For the Nth time: You should not expect locationManager.location to always have valid values immediately after calling startUpdatingLocation. You must implement the didUpdateLocations delegate method and process the location there. Don't forget to set locationManager.delegate to self or the delegate method won't get called. – Partner

Answer 1

I got it working. I've posted my code below to help anyone else having issues.

Here is my full code to get the MapKit Map View working in iOS 8.

In your AppName-Info.plist Add a new row with the key name being:

NSLocationWhenInUseUsageDescription

Or

NSLocationAlwaysUsageDescription

With the value being a string of the message that you want to be displayed:

YourAppName would like to use your location.

In your header file. (I use App Name-Prefix.pch but YourViewController.h will work too)

#define IS_OS_8_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)

YourViewController.h

#import <MapKit/MapKit.h>
#import <MapKit/MKAnnotation.h>

@interface YourViewController : UIViewController <MKMapViewDelegate,  CLLocationManagerDelegate> {

}


@property(nonatomic, retain) IBOutlet MKMapView *mapView;
@property(nonatomic, retain) CLLocationManager *locationManager;

YourViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.


    mapView.delegate = self;
    self.locationManager = [[CLLocationManager alloc] init];
    self.locationManager.delegate = self;
    #ifdef __IPHONE_8_0
    if(IS_OS_8_OR_LATER) {
         // Use one or the other, not both. Depending on what you put in info.plist
        [self.locationManager requestWhenInUseAuthorization];
        [self.locationManager requestAlwaysAuthorization];
    }
    #endif
    [self.locationManager startUpdatingLocation];

    mapView.showsUserLocation = YES;
    [mapView setMapType:MKMapTypeStandard];
    [mapView setZoomEnabled:YES];
    [mapView setScrollEnabled:YES];
}

-(void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:YES];

    self.locationManager.distanceFilter = kCLDistanceFilterNone;
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
    [self.locationManager startUpdatingLocation];
    NSLog(@"%@", [self deviceLocation]);

    //View Area
    MKCoordinateRegion region = { { 0.0, 0.0 }, { 0.0, 0.0 } };
    region.center.latitude = self.locationManager.location.coordinate.latitude;
    region.center.longitude = self.locationManager.location.coordinate.longitude;
    region.span.longitudeDelta = 0.005f;
    region.span.longitudeDelta = 0.005f;
    [mapView setRegion:region animated:YES];

}

- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation
{
    MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(userLocation.coordinate, 800, 800);
    [self.mapView setRegion:[self.mapView regionThatFits:region] animated:YES];
}
- (NSString *)deviceLocation {
    return [NSString stringWithFormat:@"latitude: %f longitude: %f", self.locationManager.location.coordinate.latitude, self.locationManager.location.coordinate.longitude];
}
- (NSString *)deviceLat {
    return [NSString stringWithFormat:@"%f", self.locationManager.location.coordinate.latitude];
}
- (NSString *)deviceLon {
    return [NSString stringWithFormat:@"%f", self.locationManager.location.coordinate.longitude];
}
- (NSString *)deviceAlt {
    return [NSString stringWithFormat:@"%f", self.locationManager.location.altitude];
}

Enjoy!

--Mike

Predella

@Predella prior ios 8 for me was enough uimapkit.showsUserLocation = YES; and mapkit delegates. Now in ios 8 should I declare CLLocationManager to request sufficient autorization? Or is there a way to force mapkit ask for sufficient permission? – Tatterdemalion

how did you get to this stuff? – Lashondalashonde

@nyekimov To my knowledge you need to call CLLocationManager to request authorization. – Predella

@FedeCugliandolo How did I get to what stuff? – Predella

Although it breaks things this is a great feature, now developers can explain why they need your location. I usually don't grant it because i don't know why is so important to know it, except for obvious apps. NSLocationWhenInUseUsageDescription is very important seems, doesn't work without. – Sayers

The above code does not compile in xcode5 & ios7: "No visible @interface for CLLocationManager declares selector 'requestWhenInUseAuthorization' " Must add #ifdef __IPHONE_8_0 – Dinner

Change where you have the if(IS_OS_8_OR_LATER){ ... } TO: #ifdef __IPHONE_8_0 if(IS_OS_8_OR_LATER) { // Use one or the other, not both. Depending on what you put in info.plist [self.locationManager requestWhenInUseAuthorization]; [self.locationManager requestAlwaysAuthorization]; } #endif – Predella

@Predella : I am following your steps, still location is 0.00, 0.000. Take a look at this question – Jailer

@Predella : I don't know what was real problem, but if I put what you have in viewDidLoad, it started working... no sure why... – Jailer

@Predella You set the delegate on locationManager before you initialize it? That does not matter anyway because there is no need to set the delegate on it, and also no need to have your viewController conform to CLLocationManagerDelegate since all you want is to call requestWhenInUseAuthorization or requestAlwaysAuthorization on an instance of CLLocationManager (according to your code). Or am I missing something – Allin

@nyekimov have you found a way to call requestAlwaysAuthorization on the mapViews locationManager, and not have to create a locationManager instance ourselves? I'm sure there is a way to do this properly for MKMapViews. – Allin

The simulator seems to have a bug that makes it appear that the location permission didn't work, so if after applying the steps in this answer it still doesn't work, try it on a device. – Rosetta

I recently face this issue and found great info at datacalculation.blogspot.in/2014/11/… – Adactylous

There is no need for the IS_IOS_8_OR_LATER macro. Simply check if the requestWhenInUseAuthorization (or requestAlwaysAuthorization) method exists. – Lasky

@Predella Its only showing blue animating circle, I need to see the country, state & city name just like google maps. Could u pls help me on that, thanks :) – Wieldy

@EshwarChaitanya If you could post a stackoverflow question so I can fully understand what you are after, I would certainly help. – Predella

@Predella Thanks a lot, but I solved my problem by setting zoom to user location and map view center coordinate property in didupdateuserlocation method, thanks once again :) – Wieldy

@Predella : NSLog(@"%@", [self deviceLocation]); not able you compile can i know what's the use of [self deviceLocation] ? – Colpitis

@satish_881 the [self deviceLocation] returns the location of the device. I log this so I can know wether or not location services is returning a GPS location. For example, if it returns "lat: 0.000000 lng: 0.000000" then I know something isn't right. Have you included the deviceLocation method? – Predella

@Predella : Yes i included , and what's happening is . In that map it's showing current location not the Lan and Longitude i'm hardcoded.! – Colpitis

@satish_881 I'm not following what your problem/question is. If you post a new stackoveroverflow detailing what the issue is, and what you are trying to achieve, I would certainly try and help you. (Just make sure to PM or comment the SO link.) – Predella

Downvote !!!! It didn't work for me. I tried this with iOS 8.3 sdk with deployment target 7.0. – Limbert

As of iOS 11, an instance of CLLocationManager is necessary only for requestWhenInUseAuthorization or requestAlwaysAuthorization and can be deallocated in [locationManager:didChangeAuthorizationStatus:]. startUpdatingLocation might be superfluous, since MKMapView keeps delivering [mapView:didUpdateUserLocation:] if you use showsUserLocation of YES. – Banlieue

Answer 2

It's not written anywhere, but if your app starts with MapKit, you will still receive the error message "Trying to start MapKit location updates without prompting for location authorization" even after implementing MBarton's answer. To avoid it, you have to create a new view controller before the MapKit, and implement the location manager delegates there. I called it AuthorizationController.

So, in AuthorizationController.h:

#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>

@interface MCIAuthorizationController : UIViewController <CLLocationManagerDelegate>

@property (strong, nonatomic) CLLocationManager *locationManager;

@end

And in AuthorizationController.m:

- (void)viewDidLoad {
    [super viewDidLoad];

    // Location manager
    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];
    }
}

#pragma mark - Location Manager delegates

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations {
    NSLog(@"didUpdateLocations: %@", [locations lastObject]);
}


- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
    NSLog(@"Location manager error: %@", error.localizedDescription);
}

- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status {
    if (status == kCLAuthorizationStatusAuthorizedWhenInUse) {
        [self.locationManager startUpdatingLocation];
        [self performSegueWithIdentifier:@"startSegue" sender:self];
    } else if (status == kCLAuthorizationStatusDenied) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Location services not authorized"
                                                        message:@"This app needs you to authorize locations services to work."
                                                       delegate:nil
                                              cancelButtonTitle:@"OK"
                                              otherButtonTitles:nil];
        [alert show];
    } else
        NSLog(@"Wrong location status");
}

Vastha

That's a very good idea. Or you check the [CLLocationManager authorizationStatus] before setting mapView.showsUserLocation = YES. This helps also to get rid of the warning. – Bellow

You don't need that extra controller, the message disappears after asking for auth and adding the plist key. – Fricassee

It disappears after the user responds to the request for authorisation. So, on the second time the app is used and afterwards the message does not appear anymore. But on the first time and while the user does not reply, the message keeps appearing. – Vastha

Checking [CLLocationManager authorizationStatus] before setting mapView.showsUserLocation = YES also is not enough. I believe the message is triggered if you do as little as declare a strong variable of CLLocation type. But I agree that creating a view controller just to avoid this is overkill. Thanks for the contributions Sebastian Wramba and @Fricassee – Vastha

Answer 3

Try This One:

 (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status {

    if (status == kCLAuthorizationStatusAuthorizedWhenInUse) {
        self.mapView.showsUserLocation = YES;
    }

Foot

Answer 4

Your code looks fine, though you do not need to call requestWhenInUseAuthorization and the other requestAlwaysAuthorization , choose one you need.

Code for displaying locations is just yet allocating locationManager, do not expect to get location data instantly.

you need to wait till delegate method gets called : -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
, then self.locationManager.location will also be set.

Cauthen

You may get some more description at datacalculation.blogspot.in/2014/11/… – Adactylous

Answer 5

Further to Mikes answer, I found that using both [self.locationManager requestWhenInUseAuthorization]; and [self.locationManager requestAlwaysAuthorization]; as demonstrated in his code does not work. You should only use ONE.

I assume some further changes were made with a more recent/stable version of the API.

Yager

He put a comment, right above those calls to choose one, and not call both. – Proclivity

It was edited since I made my post.. probably to add that comment. It certainly wasn't there initially. – Yager

I found a beginners level description at datacalculation.blogspot.in/2014/11/… – Adactylous

Answer 6

I had the same problem but adding these two line in plist file solved my problems

NSLocationWhenInUseUsageDescription

And

NSLocationAlwaysUsageDescription

NOTE : Must provide string description of both these values. You can use any of them in your controller file as below

self.locationManager= [[CLLocationManager alloc] init];
self.locationManager.delegate=self;
[self.locationManager requestAlwaysAuthorization];

You must implement CLLOcationManagerDelegate in your controller to access this functionality

Propitiatory

Answer 7

To extend the accepted answer and if you create a sample project with just the above functionality, then apart from CoreLocation and Mapkit frameworks, you might need to add UIKit, Foundation and CoreGraphics framework manually as well in Xcode 6.

Crusty

Answer 8

Actually, I am studying the CS193P Lecture 16, which is about location and map view, and I could not make the location manager work in iOS 8, applying what was in the video. Looking at your answer, I could make it work.

The Info.plist was modified as described in the answers (I use the NSLocationWhenInUseUsageDescription).

In AddPhotoViewController.hn the define was added :

#define IS_OS_8_OR_LATER ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)

In AddPhotoViewController.m, the following code was added in ViewDidLoad (after self.image):

#ifdef __IPHONE_8_0
if(IS_OS_8_OR_LATER)
{
    [self.locationManager requestWhenInUseAuthorization];
}
#endif

The authorization will be asked only once, the first time you launch the application.

The following was also added to AddPhotoViewController.h because it was not said in Lecture 16 :

@property (nonatomic) NSInteger locationErrorCode;

shouldPerformSegueWithIdentifier was modified to include else if (!self.location) :

else if (![self.titleTextField.text length])
        {
            [self alert:@"Title required"];
            return NO;
        }
        else if (!self.location)
        {
            switch (self.locationErrorCode)
            {
                case kCLErrorLocationUnknown:
                    [self alert:@"Couldn't figure out where this photo was taken (yet)."]; break;
                case kCLErrorDenied:
                    [self alert:@"Location Services disabled under Privacy in Settings application."]; break;
                case kCLErrorNetwork:
                    [self alert:@"Can't figure out where this photo is being taken.  Verify your connection to the network."]; break;
                default:
                    [self alert:@"Cant figure out where this photo is being taken, sorry."]; break;
            }
            return NO;
        }
        else
        { // should check imageURL too to be sure we could write the file
            return YES;
        }

didFailWithError was added :

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
    self.locationErrorCode = error.code;
}

Trombidiasis

In viewDidLoad, the getter of locationManager will be called. This getter does : locationManager alloc init, locationManager.delegate = self, set locationManager.desiredAccuracy to kCLLocationAccuracyBest. – Trombidiasis

Do not use the IS_OS_8_OR_LATER macro. There are proper ways to get if a method can be used or not. – Lasky