Customizing annotation pins - swift

Question

I would like to customize my annotations (pins) so I would be able to change its image. I used a function (mapview) to change the picture, so I don’t know if I should use it again to change the picture of another group of pins; let´s say I have two locations, a restaurant and a hospital, so I want to put a plate and a red cross respectively. Here is my function code:
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
if annotation is MKUserLocation {
return nil
}
var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: "identifier")
if annotationView == nil{
annotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: "identifier")
annotationView!.canShowCallout = true
annotationView!.rightCalloutAccessoryView = UIButton(type: .detailDisclosure)
let pinImg = UIImage(named: "curz")
let size = CGSize(width: 50, height: 50)
UIGraphicsBeginImageContext(size)
pinImg!.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
let resizedImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
annotationView!.image = resizedImage
}
else {
annotationView!.annotation = annotation
}
return annotationView
}

Answer 1

You can return different annotation views for different places by comparing the coordinate information. ex:
if ((annotation.coordinate.latitude == theCoordinate1.latitude)
&& (annotation.coordinate.longitude == theCoordinate1.longitude))
{
return someAnnotationView
}
follow this link Adding different images to different annotation views in xcode

Answer 2

The correct way to return different views for different annotation types (or groups of different annotation types) is to subclass the annotation and assign a different reuse identifier for each one (during init). This identifier is similar to the table view cell identifier and is used to reuse (rather than create from scratch) a cell when it scrolls out of sight. The same is true for annotations, rather than create a new one each time a 'discarded' annotation can be reused.
Then in mapview viewfor annotation you can test for annotation.identifier And assign the correct image.