ユーザーがピンをタップしたときにオブジェクトを送信したい。タイトルの送信方法しか知りませんが、一部のタイトルが同じであるため、これでは十分ではありません。
これは私のコードです:
...
- (void)viewDidLoad {
    [super viewDidLoad];
    if (context == nil) 
    { 
        context = [(AppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; 
    }
    /* ********************************************** */
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Offers" inManagedObjectContext:context];
NSFetchRequest *request = [[NSFetchRequest alloc] init];
//[request setFetchBatchSize:20];
[request setEntity:entity];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"subOffer == %@", self.subItem];
[request setPredicate:predicate];
NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:@"offerOrder" ascending:YES];
NSArray *newArray = [NSArray arrayWithObject:sort];
[request setSortDescriptors:newArray];
NSError *error;
NSMutableArray *results = [[context executeFetchRequest:request error:&error] mutableCopy];
//NSLog(@"%@", results);
/* **************************************************** */
    mapView.delegate=self;
    NSMutableArray* annotations=[[NSMutableArray alloc] init];
    CLLocationCoordinate2D theCoordinate1;
    theCoordinate1.latitude = 43.82078;
    theCoordinate1.longitude = 15.307265;
    for (Offers *offer in results){
        CLLocationCoordinate2D theCoordinate1;
        MyAnnotation* myAnnotation1=[[MyAnnotation alloc] init];
        theCoordinate1.latitude = [offer.lat doubleValue];
        theCoordinate1.longitude = [offer.lon doubleValue];
        myAnnotation1.coordinate=theCoordinate1;
        myAnnotation1.title = offer.offerName;
        myAnnotation1.subtitle = offer.offerLocation;
        [mapView addAnnotation:myAnnotation1];
        [annotations addObject:myAnnotation1];
    }//end for
    //NSLog(@"%d",[annotations count]);
    //[self gotoLocation];//to catch perticular area on screen
    // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
    // self.navigationItem.rightBarButtonItem = self.editButtonItem;
    // Walk the list of overlays and annotations and create a MKMapRect that
    // bounds all of them and store it into flyTo.
    MKMapRect flyTo = MKMapRectNull;
    for (id <MKAnnotation> annotation in annotations) {
        //NSLog(@"fly to on");
        MKMapPoint annotationPoint = MKMapPointForCoordinate(annotation.coordinate);
        MKMapRect pointRect = MKMapRectMake(annotationPoint.x, annotationPoint.y, 0, 0);
        if (MKMapRectIsNull(flyTo)) {
            flyTo = pointRect;
        } else {
            flyTo = MKMapRectUnion(flyTo, pointRect);
            //NSLog(@"else-%@",annotationPoint.x);
            //NSLog(@"else");
        }
    }
    // Position the map so that all overlays and annotations are visible on screen.
    mapView.visibleMapRect = flyTo;
    UIBarButtonItem* temp=[[UIBarButtonItem alloc] init];
    temp.title=@"Back";
    self.navigationItem.backBarButtonItem=temp;
    //[temp release];
}
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{
    // if it's the user location, just return nil.
    if ([annotation isKindOfClass:[MKUserLocation class]])
        return nil;
    // try to dequeue an existing pin view first
    static NSString* AnnotationIdentifier = @"AnnotationIdentifier";
    MKPinAnnotationView* pinView = [[MKPinAnnotationView alloc]
                                    initWithAnnotation:annotation reuseIdentifier:AnnotationIdentifier];
    pinView.animatesDrop=YES;
    pinView.canShowCallout=YES;
    pinView.pinColor=MKPinAnnotationColorRed;
    UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
    [rightButton setTitle:annotation.title forState:UIControlStateNormal];
    [rightButton addTarget:self
                    action:@selector(showDetails:)
          forControlEvents:UIControlEventTouchUpInside];
    pinView.rightCalloutAccessoryView = rightButton;
    return pinView;
}
-(IBAction)showDetails:(id)sender{
    //NSLog(@"Annotation Click");
    DetailViewController *detail = [[DetailViewController alloc] init];
    detail.title = ((UIButton*)sender).currentTitle;
    [self.navigationController pushViewController:detail animated:YES];
}
...