Question

I am trying to launch the maps app from my iPhone SDK app. Right now I can launch the maps app with directions but it goes to an overview of the directions and doesn’t use Siri and the voice navigation to give turn by turn directions.

currently I have a button that launches this code…

NSString *address = viewedObject.addressFull;
NSString *url = [NSString stringWithFormat: @"http://maps.apple.com/maps?saddr=%f,%f&daddr=%@", here.latitude, here.longitude, [address stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]];

Answer 1

With iOS 6 there’s a new way to launch maps, using openMapsWithItems: in MKMapItem. Here’s a snippet that I use that provides walking or driving directions from current location to the provided coordinates:

// iOS 6.0+ only
MKPlacemark* destPlace = [[[MKPlacemark alloc] initWithCoordinate:coordinate addressDictionary:nil] autorelease];
MKMapItem* destMapItem = [[[MKMapItem alloc] initWithPlacemark:destPlace] autorelease]; destMapItem.name = stationItem.title;

NSArray* mapItems = [[[NSArray alloc] initWithObjects: destMapItem, nil] autorelease];
NSDictionary* options = [NSDictionary dictionaryWithObjectsAndKeys:
                                 walking ? MKLaunchOptionsDirectionsModeWalking : MKLaunchOptionsDirectionsModeDriving,
                                 MKLaunchOptionsDirectionsModeKey, nil];
[MKMapItem openMapsWithItems:mapItems launchOptions:options];

The way you are doing it, which you still have to do if running on pre-iOS 6 devices, you need to include the dirflg in the URL to request walking or driving directions:

// pre iOS 6 code
NSString *urlString = [NSString stringWithFormat:@"http://maps.google.com/maps?saddr=%f,%f&daddr=%f,%f&dirflg=%c",
    currentLocation.coordinate.latitude,
    currentLocation.coordinate.longitude,
    destination.coordinate.latitude,
    destination.coordinate.longitude,
    walking ? 'w' : 'd'];