Question

When I drop a pin on my mkmapview the animation works fine and the pin drops from the top of the screen as expected. I color that pin red because I haven’t verified it. However, if I verify the pin using some code that is called on calloutAccessoryControlTapped I change the color of the Pin to green.

When I next press on the map to drop another red pin the animation fails and the pin just appears. If I do it again (long press) a new pin appears and it’s animation is fine. What could I have done to the annotation that causes this behavior.

Thanks for any insights of what could have gone wrong here…
Donie

- (MKAnnotationView *)mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>)annotation 
{

    if ([annotation isKindOfClass:[MKUserLocation class]]) 
    {
        return nil;     
    }

    static NSString * const kPinIdentifier = @"PinIdentifier";
    MKPinAnnotationView *draggablePinView = (MKPinAnnotationView *)[self.mapView dequeueReusableAnnotationViewWithIdentifier:kPinIdentifier];

    if(!draggablePinView)
    {
        draggablePinView = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:kPinIdentifier] autorelease];
        draggablePinView.pinColor = MKPinAnnotationColorRed;
        draggablePinView.animatesDrop = YES;
        draggablePinView.canShowCallout = YES;
        draggablePinView.draggable = YES;


        UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
        draggablePinView.rightCalloutAccessoryView = rightButton;
    }
    else
    {
        draggablePinView.annotation = annotation;
        draggablePinView.animatesDrop = YES;
    }
    return draggablePinView;
}


-(void)longPressGesture:(UIGestureRecognizer *)gestureRecognizer
{    
    if (gestureRecognizer.state == UIGestureRecognizerStateBegan)
    {
        CGPoint touchPoint = [gestureRecognizer locationInView:mapView];
        CLLocationCoordinate2D touchMapCoordinate = [mapView convertPoint:touchPoint toCoordinateFromView:mapView];

        [self dropPinWithCoords:touchMapCoordinate];
    }
}

- (void)mapView:(MKMapView *)mapview annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control
{        
    [self getFromServer];
}

-(void) showLoc8CodeDetail:(LOC8Code *) loc8
{
    // Open the view controller
    viewLoc8ViewController *loc8view = [[viewLoc8ViewController alloc] initWithLoc8code:loc8];
    [gMainViewController.navigationController pushViewController:loc8view animated:YES];
    [loc8view release];
}

-(void) dropPinWithCoords:(CLLocationCoordinate2D)loc
{
    // Set the loc8code from index 0 in the global array and populate from response
    LOC8Code *newPin = [gMapAnnotations objectAtIndex:0];
    newPin.starRating = 1;
    newPin.title = @"Unverified Pin";
    newPin.subtitle = @"Click to verify postcode";
    newPin.verified = NO; // this means you do have to requery if opened
    newPin.coordinate = loc;


    [self removeMapAnnotations];        
    [gMapAnnotations replaceObjectAtIndex:1 withObject:newPin];
    [self.mapView addAnnotation:[gMapAnnotations objectAtIndex:1]];

    // Reset flags
    [dropPinButton setTitle:@"Replace Pin" forState:UIControlStateNormal];
    [self moveAndHidePinButtons:NO];
}
-(void)getFromServer
{
    [self checkRegisteredFromServer]; // Does API call to see if device already registered

    // Get the loc8 code from the global array (pin always index 1)
    LOC8Code *loc8 = [gMapAnnotations objectAtIndex:1];

    // If we have a verified pin already (from a search) just show the info
    if(loc8.verified == YES)
    {
        [self showLoc8CodeDetail:loc8];
    }
    else
    {
        [self setSpinning:YES];
        // Get coordinates
        NSString *urlWithCoords = [NSString stringWithFormat:@"https://www.server.com/api/rest/lite/loc?t=%@&u=%@&a=iloc8er&la=%f&lo=%f", 
                                    [Util getAPIToken], [UIDevice currentDevice].uniqueIdentifier, 
                                    loc8.coordinate.latitude,
                                    loc8.coordinate.longitude];
        NSLog(@"%@", urlWithCoords);
        ASIHTTPRequest *request = [self populateRequest:request withURL: urlWithCoords];
        [request setDidFinishSelector:@selector(loc8returned:)];
        [[self networkQueue] addOperation:request]; 
    }
}

-(void)loc8returned:(ASIHTTPRequest *)request
{
    @try 
    {    
        NSString *response = [request responseString];
        NSLog(@"RSP: %@", response);

        // Store incoming data into an NSDictionary
        SBJsonParser *parser = [[SBJsonParser new]autorelease];
        NSDictionary *results = [parser objectWithString:response error:nil];

        // Check for errors
        NSNumber *r = [results objectForKey:@"r"];
        NSString *e = [results valueForKey:@"e"];

        if(r.boolValue == NO)
        {
            if([e isEqualToString:@"lc51"] || [e isEqualToString:@"lc52"])
            {
                // Outside range
                [self setSpinning:NO];
                return;
            }

            if([e isEqualToString:@"ud04"])
            {
                // quota check
                [self setSpinning:NO];
                return;
            }
        }
        else
        {
            LOC8Code *loc8 = [gMapAnnotations objectAtIndex:1];

            // Set the loc8code
            NSString *lc = [results valueForKey:@"lc"];
            loc8.postcode = lc;
            loc8.verified = YES;
            loc8.starRating = 0;
            loc8.title = lc;


            // This pin is now validated
            MKPinAnnotationView *pinView = (MKPinAnnotationView*)[mapView viewForAnnotation:[gMapAnnotations objectAtIndex:1]];
            pinView.pinColor = MKPinAnnotationColorGreen;

            // Open the view controller
            [self showLoc8CodeDetail:loc8];
        }
    }
    @catch (NSException *exception) 
    {
        [Util say:@"Service Temporarily Unavailable (-200):"];
        NSLog(@"RSP: %@, %@", [exception name], [exception reason]);
    }
    [self setSpinning:NO];
}

The loc8code header class is defined as follows:

@interface LOC8Code : MKPlacemark {
    NSString *postcode;
    NSString *BusinessName;
    int starRating;
    CLLocationCoordinate2D coordinate_;
    NSString *title_;
    NSString *subtitle_;
    BOOL verified;          // Verified locations can't be moved (if pin moved then flag as not verified)
}

// Re-declare MKAnnotation's readonly property 'coordinate' to readwrite. 

@property (nonatomic, retain) NSString *postcode;
@property (nonatomic, retain) NSString *BusinessName;
@property (nonatomic, assign) int starRating;
@property (nonatomic, readwrite, assign) CLLocationCoordinate2D coordinate;
@property (nonatomic, retain) NSString *title;
@property (nonatomic, retain) NSString *subtitle;
@property (nonatomic, assign) BOOL verified;

@end

And the implementation

#import "LOC8Code.h"

@implementation LOC8Code

@synthesize coordinate = coordinate_;
@synthesize title = title_;
@synthesize subtitle = subtitle_;
@synthesize verified;
@synthesize starRating;
@synthesize postcode;
@synthesize BusinessName;


- (id)initWithCoordinate:(CLLocationCoordinate2D)coordinate addressDictionary:(NSDictionary *)addressDictionary {

    if ((self = [super initWithCoordinate:coordinate addressDictionary:addressDictionary])) {
        self.coordinate = coordinate;
    }
    return self;
}

- (void)dealloc {
    [title_ release];
    [subtitle_ release];
    [postcode release];
    [BusinessName release];

    [super dealloc];
}

@end

Answer 1

It’s probably due to the fact you’re using the same reuse identifier all the time. Check out this line: static NSString * const kPinIdentifier = @"PinIdentifier";

That value needs to be unique for each pin you drop if all these pins are going to be different. I often use a comma-separated string of the latitude and longitude of a marker for my identifiers.