MKAnnotations not showing up until I scroll the map - iphone

Question

Well, I have a view with a map where I load some annotations. Everything works fine, but when I want to erase those annotations and include other annotations they do not show up until I move (scroll) the map.
Any suggestion?
EDITED:
Seems like instead of using this:
[self updateMap];
I have to use:
[self performSelectorOnMainThread:#selector(updateMap) withObject:nil waitUntilDone:true];
Being update map the method where I add my new annotations.

Answer 1

Try smth like this:
[mapView removeAnnotations:[mapView annotations]];
NSArray *targetArray = /*YOUR ARRAY NAME with object, containing `latitude`, `longitude` and `title` values*/
for (id *item in targetArray) {
if (item.latitude && item.longitude) {
MKPin *pin = [[MKPin alloc] init]; // MKPin is your class which specifies the deledate `MKAnnotation`
pin.coordinate = CLLocationCoordinate2DMake(item.latitude, item.longitude);
pin.title = item.title;
[mapView addAnnotation:pin];
}
}

Answer 2

In the viewdidload use :
- (void)viewDidLoad
{
NSMutableArray* annotations=[[NSMutableArray alloc] init];
MyAnnotation* myAnnotation = [[MyAnnotation alloc] init];
myAnnotation.coordinate = theCoordinate;
[annotations addObject:myAnnotation];
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);
}
}
// Position the map so that all overlays and annotations are visible on screen.
mapView.visibleMapRect = flyTo;
}
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{
NSLog(#"welcome into the map view 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] autorelease];
pinView.animatesDrop=YES;
pinView.canShowCallout=YES;
pinView.draggable = NO;
pinView.pinColor=MKPinAnnotationColorGreen;
//button on the right for popup for pins
UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[rightButton setTitle:annotation.title forState:UIControlStateNormal];
[rightButton addTarget:self
action:#selector(showDetails:)
forControlEvents:UIControlEventTouchUpInside];
pinView.rightCalloutAccessoryView = rightButton;
//zoom button on the left of popup for pins
UIButton* leftButton = [UIButton buttonWithType:UIButtonTypeContactAdd];
[leftButton setTitle:annotation.title forState:UIControlStateNormal];
[leftButton addTarget:self
action:#selector(zoomToLocation:) forControlEvents:UIControlEventTouchUpInside];
pinView.leftCalloutAccessoryView = leftButton;
UIImageView *profileIconView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"profile.png"]];
pinView.leftCalloutAccessoryView = profileIconView;
[profileIconView release];
return pinView;
}
Hopefully this helps !!!!!!!!!