Opening maps with current location and directions in iOS 6

Question

I am building an app that can open the Maps app with directions from the user's current position to another position. The code looks like this:

- (id)resolveDirectionsFromCoordinate:(CLLocationCoordinate2D)startCoordinate toCoordinate:(CLLocationCoordinate2D)endCoordinate
{
    NSString* url = [NSString stringWithFormat: @"http://maps.google.com/maps?saddr=%f,%f&daddr=%f,%f",
                 startCoordinate.latitude, startCoordinate.longitude,
                 endCoordinate.latitude, endCoordinate.longitude];
    [[UIApplication sharedApplication] openURL: [NSURL URLWithString: url]];

    return nil;
}

Thos works well in iOS 5.x. In iOS 6, however, this brings up Safari instead, since Maps no longer uses Google Maps.

Does anyone know which URL I should call in iOS 6?

Answer 1

The Apple Documentation recommends using the equivalent maps.apple.com URL Scheme

so use

http://maps.apple.com/maps?saddr=%f,%f&daddr=%f,%f

instead of

http://maps.google.com/maps?saddr=%f,%f&daddr=%f,%f

to be backwards compatible your code would be

    NSString* versionNum = [[UIDevice currentDevice] systemVersion];
    NSString *nativeMapScheme = @"maps.apple.com";
    if ([versionNum compare:@"6.0" options:NSNumericSearch] == NSOrderedAscending){
        nativeMapScheme = @"maps.google.com";
    }
    NSString* url = [NSString stringWithFormat: @"http://%@/maps?saddr=%f,%f&daddr=%f,%f", nativeMapScheme startCoordinate.latitude, startCoordinate.longitude,
                 endCoordinate.latitude, endCoordinate.longitude];
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]]; 

Alternatively you could also use the maps://saddr=%f,%f&daddr=%f,%fscheme but it does not appear support the full range of parameters.

Answer 2

Use + (BOOL)openMapsWithItems:(NSArray *)mapItems launchOptions:(NSDictionary *)launchOptions method. From the MKMapItem Class Reference :

You use this method to pass one or more map items to the Maps app. For example, you might use this method to ask the Maps app to display location-based search results generated by your app. Maps displays pins at each location you specify and uses the contents of each map item object to display additional information.

Answer 3

// Check for iOS 6
Class mapItemClass = [MKMapItem class];
if (mapItemClass && [mapItemClass     respondsToSelector:@selector(openMapsWithItems:launchOptions:)]) 
{
    // Create an MKMapItem to pass to the Maps app
    CLLocationCoordinate2D coordinate = 
                CLLocationCoordinate2DMake(16.775, -3.009);
    MKPlacemark *placemark = [[MKPlacemark alloc] initWithCoordinate:coordinate 
                                        addressDictionary:nil];
    MKMapItem *mapItem = [[MKMapItem alloc] initWithPlacemark:placemark];
    [mapItem setName:@"My Place"];

    // Set the directions mode to "Driving"
    // Can use MKLaunchOptionsDirectionsModeWalking instead
    NSDictionary *launchOptions = @{MKLaunchOptionsDirectionsModeKey :   MKLaunchOptionsDirectionsModeDriving };
    // Get the "Current User Location" MKMapItem
    MKMapItem *currentLocationMapItem = [MKMapItem mapItemForCurrentLocation];
   // Pass the current location and destination map items to the Maps app
   // Set the direction mode in the launchOptions dictionary
   [MKMapItem openMapsWithItems:@[currentLocationMapItem, mapItem] 
                launchOptions:launchOptions];
   }

That is all :)

Answer 4

I recommend checking out CMMapLauncher, a mini-library that I built to launch Apple, Google, and other iOS mapping apps with a specific mapping request. With CMMapLauncher, the code to get the directions in your question would be:

[CMMapLauncher launchMapApp:CMMapAppAppleMaps
          forDirectionsFrom:[CMMapPoint mapPointWithName:@"Origin"
                                              coordinate:startCoordinate]
                         to:[CMMapPoint mapPointWithName:@"Destination"
                                              coordinate:endCoordinate]];

As you can see, it also encapsulates the version checking required between iOS 6 & others.