Check whether zoom level changed

Question

I\'m using MapKit on iPhone. How can I know when the user changes the zoom level (zoom in\\out the map)?

I\'ve tried to use mapView:(MKMapView *)mapView regi

Answer 1

I found this very helpful and developed the following code based on these answers.

- (void)mapView:(MKMapView *)mapView regionWillChangeAnimated:(BOOL)animated 
{
   mapRegion = self.mapView.region;
}


-(void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated{

MKCoordinateRegion newRegion = self.mapView.region;

NSInteger zFactor;
if ((mapRegion.span.latitudeDelta/newRegion.span.latitudeDelta) > 1.5){
    NSLog(@"Zoom in changed");
    zFactor = 20;
    CustomPlacemark *aO; 
    MKAnnotationView *aV; 
    for (aO in self.mapView.annotations) {
        aV = [[self mapView] viewForAnnotation:aO];
        aV.frame = CGRectMake(aV.frame.origin.x, aV.frame.origin.y, aV.frame.size.width+zFactor, aV.frame.size.height+zFactor);
        [[[self mapView] viewForAnnotation:aO] setFrame:aV.frame];
    }
}
if ((mapRegion.span.latitudeDelta/newRegion.span.latitudeDelta) < 0.75){
    NSLog(@"Zoom out");
    zFactor = -20;
    CustomPlacemark *aO; 
    MKAnnotationView *aV; 
    for (aO in self.mapView.annotations) {
        aV = [[self mapView] viewForAnnotation:aO];
        aV.frame = CGRectMake(aV.frame.origin.x, aV.frame.origin.y, aV.frame.size.width+zFactor, aV.frame.size.height+zFactor);
        [[[self mapView] viewForAnnotation:aO] setFrame:aV.frame];
    }
  }
}