[Newbie help] why I realized MKAnnotation agreement does not call my mapView: viewForAnnotation it

If that
Code:

 

customAnnotation.h 
@ Interface customAnnotation: NSObject  
{
CLLocationCoordinate2D coordinate; 
NSString * title; 
NSString * subtitle; 
} 

@ Property (nonatomic, readonly) CLLocationCoordinate2D coordinate; 
@ Property (nonatomic, retain) NSString * title; 
@ Property (nonatomic, retain) NSString * subtitle; 
- (Id) initCustomeAnnotation: (CLLocationCoordinate2D) coords; 

customAnnotation.m 
@ Implementation customAnnotation 
@ Synthesize coordinate, title, subtitle; 

- (Id) initCustomeAnnotation: (CLLocationCoordinate2D) coords {

if (self = [super init]) {
coordinate = coords; 
} 

return self; 
} 


- (Void) dealloc {
[Self.title release]; 
[Self.subtitle release]; 
[Super dealloc]; 
} 


@ End 

viewController.m 

@ Implementation ipadMapViewController 

- (MKAnnotationView *) mapView: (MKMapView *) theMapView viewForAnnotation: (id ) annotation {

MKPinAnnotationView * pinView = (MKPinAnnotationView *) [theMapView dequeueReusableAnnotationViewWithIdentifier: annotation.title]; 

if (pinView == nil) {
pinView = [[[MKPinAnnotationView alloc] initWithAnnotation: annotation reuseIdentifier: annotation.title] autorelease]; 
pinView.animatesDrop = YES; 
pinView.canShowCallout = YES; 
pinView.pinColor = MKPinAnnotationColorGreen; 
} 
else {
pinView.annotation = annotation; 
} 

NSLog (@ "set green"); 
return pinView; 
} 

- (IBAction) buttonPressed: (id) sender {

CLLocationCoordinate2D coords; 
coords.latitude = 37.331689; 
coords.longitude = 122.030731; 
float zoomLevel = 0.018; 

MKCoordinateRegion region = MKCoordinateRegionMake (coords, MKCoordinateSpanMake (zoomLevel, zoomLevel)); 
[PmapView setRegion: [pmapView regionThatFits: region] animated: YES]; 

customAnnotation * annotation = [[customAnnotation alloc] initCustomeAnnotation: coords]; 
annotation.title = @ "Apple"; 
annotation.subtitle = @ "Subtitle"; 

[PmapView addAnnotation: annotation]; 
[Annotation release]; 
} 
............ 

@ End 

pin color change, the effect of falling can not get out
Reply:
Forgotten by the original sentence mapView.delegate = self
Reply:

Reply:
Details are important
Reply:
I just encountered this problem, see this article solved, newbie questions