Calculating routes with multiple pins - iphone

Question

In my application I have a mapView with several custom pins.
I'm trying to do this: On the showCallout an AlertView appears and tells if you want to calculate the route. This works but just for one location. Or better, only one method gets called, so I've only one destination.
Here's my code (I have 9 destinations, but I post only 2 to make the code shorter):
- (void)viewDidLoad
{
[super viewDidLoad];
[mapView setMapType:MKMapTypeStandard];
[mapView setZoomEnabled:YES];
[mapView setScrollEnabled:YES];
[mapView setDelegate:(id)self];
MKCoordinateRegion TavernaCongiura = { {0.0, 0.0} , {0.0, 0.0} };
TavernaCongiura.center.latitude = 40.380784;
TavernaCongiura.center.longitude = 15.541373;
TavernaCongiura.span.longitudeDelta = 0.004f;
TavernaCongiura.span.latitudeDelta = 0.004f;
[mapView setRegion:TavernaCongiura animated:YES];
mapView.showsUserLocation = YES;
TeggianoAnnotation *ann0 = [[TeggianoAnnotation alloc] init];
ann0.title = #"Taverna de la Congiura";
ann0.subtitle = #"Antipasto";
ann0.coordinate = TavernaCongiura.center;
[mapView addAnnotation: ann0];
MKCoordinateRegion TavernaDeiMori = { {0.0, 0.0} , {0.0, 0.0} };
TavernaDeiMori.center.latitude = 40.380535;
TavernaDeiMori.center.longitude = 15.542028;
TavernaDeiMori.span.longitudeDelta = 0.004f;
TavernaDeiMori.span.latitudeDelta = 0.004f;
[mapView setRegion:TavernaDeiMori animated:YES];
TeggianoAnnotation *ann1 = [[TeggianoAnnotation alloc] init];
ann1.title = #"Taverna dei Mori";
ann1.subtitle = #"Parmatieddi";
ann1.coordinate = TavernaDeiMori.center;
[mapView addAnnotation: ann1];
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation
*)newLocation fromLocation:(CLLocation *)oldLocation {
if (newLocation.horizontalAccuracy == oldLocation.horizontalAccuracy) {
[self->locationManager stopUpdatingLocation];
CLLocationCoordinate2D coords = newLocation.coordinate;
NSString *stringURL = [NSString stringWithFormat:#"http://maps.google.com
/maps?saddr=%g,%g&daddr=40.380784,15.541373", coords.latitude, coords.longitude];
NSURL *url = [NSURL URLWithString:stringURL];
[[UIApplication sharedApplication] openURL:url];
}
}
- (void)locationManagerMori:(CLLocationManager *)manager didUpdateToLocation:
(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
if (newLocation.horizontalAccuracy == oldLocation.horizontalAccuracy) {
[self->locationManager stopUpdatingLocation];
CLLocationCoordinate2D coords = newLocation.coordinate;
NSString *stringURL = [NSString stringWithFormat:#"http://maps.google.com
/maps?saddr=%g,%g&daddr=40.380535,15.542028", coords.latitude, coords.longitude];
NSURL *url = [NSURL URLWithString:stringURL];
[[UIApplication sharedApplication] openURL:url];
}
}
-(MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:
(id<MKAnnotation>)annotation {
MKAnnotationView *MyPin=[[MKAnnotationView alloc] initWithAnnotation:annotation
reuseIdentifier:#"current"];
UIButton *advertButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
if ([[annotation title] isEqualToString:#"Taverna de la Congiura"]) {
[advertButton addTarget:self action:#selector(buttonCongiura:)
forControlEvents:UIControlEventTouchUpInside];
MyPin.image = [UIImage imageNamed:#"CongiuraMappa.png"];
}
if ([[annotation title] isEqualToString:#"Taverna dei Mori"]) {
[advertButton addTarget:self action:#selector(buttonMori:)
forControlEvents:UIControlEventTouchUpInside];
MyPin.image = [UIImage imageNamed:#"MoriMappa.png"];
}
MyPin.rightCalloutAccessoryView = advertButton;
MyPin.draggable = NO;
MyPin.highlighted = YES;
MyPin.canShowCallout = YES;
return MyPin;
}
-(void)buttonCongiura:(id)sender {
UIAlertView *alertViewCongiura;
alertViewCongiura = [[UIAlertView alloc] initWithTitle:#"Taverna de la Congiura"
message:#"Calcola Percorso" delegate:self cancelButtonTitle:#"Annulla"
otherButtonTitles:#"Calcola", nil];
[alertViewCongiura show];
}
-(void)buttonMori:(id)sender {
UIAlertView *alertViewMori;
alertViewMori = [[UIAlertView alloc] initWithTitle:#"Taverna dei Mori"
message:#"Calcola Percorso" delegate:self cancelButtonTitle:#"Annulla"
otherButtonTitles:#"Calcola", nil];
[alertViewMori show];
}
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 1) {
self->locationManager = [[CLLocationManager alloc] init];
self->locationManager.delegate = (id)self;
[self->locationManager startUpdatingLocation];
}
if (buttonIndex == 2) {
self->locationManagerMori = [[CLLocationManager alloc] init];
self->locationManagerMori.delegate = (id)self;
[self->locationManagerMori startUpdatingLocation];
}
}
The problem is that only the first
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation
*)newLocation fromLocation:(CLLocation *)oldLocation
is called.

Answer 1

You can't use a different name for the delegate methods for each of the location manager instances you are using. Each location manager will still call the methods defined by the CLLocationManagerDelegate protocol.
You could check which manager is calling by checking if the manager parameter is equal to one of the instances you are creating (eg. if (manager == locationManagerMori)).
But you don't need to create a separate location manager instance for each annotation in the first place.
Instead, keep just one location manager instance and in the delegate method, you can find out what the currently selected annotation is and use its coordinates in the url string. For example:
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation
{
if (newLocation.horizontalAccuracy == oldLocation.horizontalAccuracy)
//the above if-condition looks a little suspicious by the way
{
if (mapView.selectedAnnotations.count == 0)
{
//no annotation selected, do nothing
return;
}
//there can only be one selected annotation so get the one at index 0
id<MKAnnotation> selectedAnnotation =
[mapView.selectedAnnotations objectAtIndex:0];
[self->locationManager stopUpdatingLocation];
CLLocationCoordinate2D coords = newLocation.coordinate;
NSString *stringURL = [NSString stringWithFormat:
#"http://maps.google.com/maps?saddr=%g,%g&daddr=%g,%g",
coords.latitude, coords.longitude,
selectedAnnotation.coordinate.latitude,
selectedAnnotation.coordinate.longitude];
NSURL *url = [NSURL URLWithString:stringURL];
//stop updating location to avoid possible endless loop
//when user comes back to this app...
[manager stopUpdatingLocation];
[[UIApplication sharedApplication] openURL:url];
}
}
You also don't need a separate button action method for each annotation. You can just create one button action method and use the same technique to get the selected annotation.
Another issue is in the alert view clickedButtonAtIndex method. You seem to be checking which annotation it is by looking at the alert view's button index. That index will be either the Annulla or Calcola button (not which annotation).
Since you won't need to create a separate location manager for each annotation, you won't need to know which annotation the alert view is for. You just need to check whether the user tapped Annulla or Calcola:
if (buttonIndex == alertView.firstOtherButtonIndex)
{
self->locationManager = [[CLLocationManager alloc] init];
self->locationManager.delegate = (id)self;
self->locationManager startUpdatingLocation];
}