Fitting annotations on a MKMapView while keeping user position centered

Question

I\'m trying to fit all annotations on my MKMapView while keeping the current user position in center of map.

There are already many references[1][2] on how

Answer 1

I found this solution to be the most reliable and @Anna suggested it as well so it might be an ok solution.

This is my method (implemented as a method of my inherited MKMapView

- (void)fitAnnotationsKeepingCenter {
  CLLocation *centerLocation = [[CLLocation alloc]
    initWithLatitude:self.centerCoordinate.latitude
    longitude:self.centerCoordinate.longitude];

  // starting distance (do not zoom less than this)
  CLLocationDistance maxDistance = 350;

  for (id <MKAnnotation> vehicleAnnotation in [self annotations]) {
    CLLocation *annotationLocation = [[CLLocation alloc] initWithLatitude:vehicleAnnotation.coordinate.latitude longitude:vehicleAnnotation.coordinate.longitude];
    maxDistance = MAX(maxDistance, [centerLocation distanceFromLocation:annotationLocation]);
  }

  MKCoordinateRegion fittedRegion = MKCoordinateRegionMakeWithDistance(centerLocation.coordinate, maxDistance * 2, maxDistance * 2);
  fittedRegion = [self regionThatFits:fittedRegion];
  fittedRegion.span.latitudeDelta *= 1.2;
  fittedRegion.span.longitudeDelta *= 1.2;

  [self setRegion:fittedRegion animated:YES];
}