iPhone Mapkit adding custom image and pins to annotations

Question

I am trying to change the pin colour from the default red to a custom image but whatever I am trying just isn't working.

I have downloaded the sample code from this website:

http://icodeblog.com/2009/12/21/introduction-to-mapkit-in-iphone-os-3-0/

The code works on it's own but when I import the annotation classes into my code, they do not work and I have no idea why. I have also tried a number of different methods from other sites but I can't even get the pin colour to change.

My project has 4 tabs and the MapView is on one of the tabs. When I select it, it parses a JSON string and adds the separate annotations onto the map. i have the title and subtitle showing up when I click on the pin, but cannot change the colour or image.

Here is how I add my annotations - MapAnnotation follows MKAnnotation:

MapAnnotation *ann = [[MapAnnotation alloc] initWithCoordinate:newCoord];
    ann.title = [locationDictionary objectForKey:@"name"];
    ann.subtitle = [locationDictionary objectForKey:@"name"];

    [mapView addAnnotation:ann];
    [ann release]

Here is how I try and attempt to change the colour - I have MapView.delegate=self in the view controller:

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation{
MKPinAnnotationView *pin = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:[annotation title]];

if (pin == nil) {
    pin = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:[annotation title]] autorelease];
}else {
    pin.annotation = annotation;
}

pin.pinColor = MKPinAnnotationColorGreen;
pin.animatesDrop = YES;
pin.canShowCallout = TRUE;
return pin;

}

I get the annotations to appear with title and subtitle, just not green markers. They're always red wether I use colours or images. If anyone could help me out, that would be great!

Thanks

EDIT:

The mapView delegate is assigned in the viewDidLoad method. I also add an Overlay to a certain part of the map. This is working fine, I have also taken it out and tried it without that incase it was causing a problem but it still didn't fix it.

- (void)viewDidLoad {
[super viewDidLoad];

MKCoordinateRegion cordRgn;

LusuAppAppDelegate *delegate =[[UIApplication sharedApplication]delegate];

if (delegate.CurrentLocation == 0) {
    cordRgn.center.latitude = (CENTRE_OF_POSITION_2_LAT);
    cordRgn.center.longitude = (CENTRE_OF_POSITION_2_LON);
    delegate.CurrentLocation = 1;
}else if (delegate.CurrentLocation == 1) {
    cordRgn.center.latitude = (CENTRE_OF_POSITION_1_LAT);
    cordRgn.center.longitude = (CENTRE_OF_POSITION_1_LON);  
    delegate.CurrentLocation = 0;
}

cordRgn.span.latitudeDelta = 0.009f;
cordRgn.span.longitudeDelta = 0.009f;


self.locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;

[locationManager startUpdatingLocation];
[locationManager startUpdatingHeading];

//add overlay
MKRasterOverlay *overlay = [[MKRasterOverlay alloc] init];
[overlay setCoordinate:CLLocationCoordinate2DMake(54.005508, -2.780507)];

MKMapRect mkrect;
MKMapPoint mkpointa, mkpointb;
mkrect.origin = MKMapPointForCoordinate(CLLocationCoordinate2DMake(54.016964, -2.794862));
mkpointa = MKMapPointForCoordinate(CLLocationCoordinate2DMake(54.016964, 2.000000));
mkpointb = MKMapPointForCoordinate(CLLocationCoordinate2DMake(54.001447, 2.013770));
mkrect.size.width = mkpointb.x - mkpointa.x;
mkrect.size.height = mkpointb.y - mkpointa.y;
overlay.boundingMapRect = mkrect;

mapView.delegate = self;

[mapView addOverlay:overlay];
[mapView setRegion:cordRgn animated:NO];
[self.mapView setShowsUserLocation:YES];

[self doAnnotations];

}

The doAnnotations function is the code shown above but in a loop. Thanks again for your help.

Solution

Your code looks fine to me. I suspect you have an error in your delegate assignment and mapView:viewForAnimation is not actually being called. An MKMapView without a delegate providing that function will work fine, with red pins for all annotations. Try adding some NSLog statements or setting a breakpoint in the debugger to make sure you're actually executing this code.

You probably already know this, but using your own images will require you to create pins that are MKAnnotationViews rather than MKAnnotationPinViews.