viewForAnnotation not working as implemented

[i.konov]

hello,

I'm developing a view controller for a map. I want to show just one location and drop pin in the center of the map where the location is. But somehow the viewForAnnotation method does not work. Here is my code:

#import "VenueMap.h"
#import "VenueAnnotation.h"


@implementation VenueMap

@synthesize mapView;
@synthesize mapVenue;

#pragma mark -

- (void)showVenueLocation {
	CLLocation *loc = [[CLLocation alloc] initWithLatitude:[mapVenue.latitude doubleValue] longitude:[mapVenue.longitude doubleValue]];
	
	MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(loc.coordinate, 300, 300);
	MKCoordinateRegion adjustedRegion = [mapView regionThatFits:viewRegion];
	[mapView setRegion:adjustedRegion animated: YES];
	
	VenueAnnotation *an = [[VenueAnnotation alloc] init];
	an.venueName = mapVenue.name;
	an.venueAddress = mapVenue.address;
	an.venueType = mapVenue.venuetype;
	an.coordinate = loc.coordinate;

	[mapView addAnnotation:an];

	[an release];
	[loc release];
}

- (IBAction)showUserLocation {
	NSLog(@"Entering %s", __FUNCTION__);
}

- (void)openCallout:(id <MKAnnotation>)annotation {
	[mapView selectAnnotation:annotation animated:YES];
}

#pragma mark -

- (void)viewDidLoad {
	mapView.mapType = MKMapTypeStandard;
	self.title = mapVenue.name;
	
	UIBarButtonItem *userLocationButton =	[[UIBarButtonItem alloc]
									 initWithTitle:@"Loc"
									 style:UIBarButtonItemStylePlain
									 target:self
									 action:@selector(showUserLocation:)];
	self.navigationItem.rightBarButtonItem = userLocationButton;
	[userLocationButton release];
	
	[super viewDidLoad];
}

- (void)viewDidAppear:(BOOL)animated {
	[self showVenueLocation];
}

- (void)didReceiveMemoryWarning {
	// Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
	
	// Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
	self.mapView = nil;
	self.mapVenue = nil;
}


- (void)dealloc {
	[mapView release];
	[mapVenue release];
    [super dealloc];
}

#pragma mark -
#pragma mark Map View Delegate Methods

- (MKAnnotationView *) mapView:(MKMapView *)theMapView viewForAnnotation:(id <MKAnnotation>) annotation {
    static NSString *placemarkIdentifier = @"Map Location Identifier";
    if ([annotation isKindOfClass:[VenueAnnotation class]]) {
        MKPinAnnotationView *annotationView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:placemarkIdentifier];
        if (annotationView == nil)  {
            annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:placemarkIdentifier];
        }            
        else 
            annotationView.annotation = annotation;
        
        annotationView.enabled = YES;
        annotationView.animatesDrop = YES;
        annotationView.pinColor = MKPinAnnotationColorPurple;
        annotationView.canShowCallout = YES;
        [self performSelector:@selector(openCallout:) withObject:annotation afterDelay:0.5];
        
		return annotationView;
    }
    return nil;
}

- (void)mapViewDidFailLoadingMap:(MKMapView *)theMapView withError:(NSError *)error {
    UIAlertView *alert = [[UIAlertView alloc] 
                          initWithTitle:NSLocalizedString(@"Error loading map", @"Error loading map")
                          message:[error localizedDescription] 
                          delegate:nil 
                          cancelButtonTitle:NSLocalizedString(@"Okay", @"Okay") 
                          otherButtonTitles:nil];
    [alert show];
    [alert release];
}

@end

it shows the annotation but just with the regular red pin, not animating the drop and not opening the callout. any suggestions why?

[tigermain]

Originally Posted by i.konov

hello,

I'm developing a view controller for a map. I want to show just one location and drop pin in the center of the map where the location is. But somehow the viewForAnnotation method does not work. Here is my code:

#import "VenueMap.h"
#import "VenueAnnotation.h"


@implementation VenueMap

@synthesize mapView;
@synthesize mapVenue;

#pragma mark -

- (void)showVenueLocation {
	CLLocation *loc = [[CLLocation alloc] initWithLatitude:[mapVenue.latitude doubleValue] longitude:[mapVenue.longitude doubleValue]];
	
	MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(loc.coordinate, 300, 300);
	MKCoordinateRegion adjustedRegion = [mapView regionThatFits:viewRegion];
	[mapView setRegion:adjustedRegion animated: YES];
	
	VenueAnnotation *an = [[VenueAnnotation alloc] init];
	an.venueName = mapVenue.name;
	an.venueAddress = mapVenue.address;
	an.venueType = mapVenue.venuetype;
	an.coordinate = loc.coordinate;

	[mapView addAnnotation:an];

	[an release];
	[loc release];
}

- (IBAction)showUserLocation {
	NSLog(@"Entering %s", __FUNCTION__);
}

- (void)openCallout:(id <MKAnnotation>)annotation {
	[mapView selectAnnotation:annotation animated:YES];
}

#pragma mark -

- (void)viewDidLoad {
	mapView.mapType = MKMapTypeStandard;
	self.title = mapVenue.name;
	
	UIBarButtonItem *userLocationButton =	[[UIBarButtonItem alloc]
									 initWithTitle:@"Loc"
									 style:UIBarButtonItemStylePlain
									 target:self
									 action:@selector(showUserLocation:)];
	self.navigationItem.rightBarButtonItem = userLocationButton;
	[userLocationButton release];
	
	[super viewDidLoad];
}

- (void)viewDidAppear:(BOOL)animated {
	[self showVenueLocation];
}

- (void)didReceiveMemoryWarning {
	// Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
	
	// Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
	self.mapView = nil;
	self.mapVenue = nil;
}


- (void)dealloc {
	[mapView release];
	[mapVenue release];
    [super dealloc];
}

#pragma mark -
#pragma mark Map View Delegate Methods

- (MKAnnotationView *) mapView:(MKMapView *)theMapView viewForAnnotation:(id <MKAnnotation>) annotation {
    static NSString *placemarkIdentifier = @"Map Location Identifier";
    if ([annotation isKindOfClass:[VenueAnnotation class]]) {
        MKPinAnnotationView *annotationView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:placemarkIdentifier];
        if (annotationView == nil)  {
            annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:placemarkIdentifier];
        }            
        else 
            annotationView.annotation = annotation;
        
        annotationView.enabled = YES;
        annotationView.animatesDrop = YES;
        annotationView.pinColor = MKPinAnnotationColorPurple;
        annotationView.canShowCallout = YES;
        [self performSelector:@selector(openCallout:) withObject:annotation afterDelay:0.5];
        
		return annotationView;
    }
    return nil;
}

- (void)mapViewDidFailLoadingMap:(MKMapView *)theMapView withError:(NSError *)error {
    UIAlertView *alert = [[UIAlertView alloc] 
                          initWithTitle:NSLocalizedString(@"Error loading map", @"Error loading map")
                          message:[error localizedDescription] 
                          delegate:nil 
                          cancelButtonTitle:NSLocalizedString(@"Okay", @"Okay") 
                          otherButtonTitles:nil];
    [alert show];
    [alert release];
}

@end

it shows the annotation but just with the regular red pin, not animating the drop and not opening the callout. any suggestions why?

I assume you'[ve probably fixed this, but I would suggest that you havent set the delegate of the mapview to self