How do I add button to MKPointAnnotation in Swift

Question

I want to add a button that is going to appear on the right of the annotation when a user tapped on a marker. Here's currently what I'm doing.

1. Download a json file from my website.
2. Open the file and parse it.
3. Plot all the markers using coords from the json file
4. But now..how do I add a button to the right of my annotation that will move to a detailViewController when a user tap it?

here's my ViewDidLoad

//Retrieve the existing JSON from document directory
        let defaults = UserDefaults.standard
        let fileUrl = defaults.url(forKey: "pathForJSON")
        do {
            let jsonData = try Data(contentsOf: fileUrl!, options: [])
            let myJson = try JSONSerialization.jsonObject(with: jsonData, options: .mutableContainers) as! [Dictionary<String,AnyObject>]
            // print out the content
//            print("My JSON: ", myJson)
            createAnnotation(locations: myJson)
        } catch {
            print(error)
        }

My createAnnotation function.

func createAnnotation(locations: [Dictionary<String, AnyObject>]) {
        for location in locations {
            let annotation = MKPointAnnotation()
            annotation.title = location["name"] as? String
            let lat = (location["latitude"] as! NSString).doubleValue
            let lon = (location["longitude"] as! NSString).doubleValue
            annotation.coordinate = CLLocationCoordinate2D(latitude: lat, longitude: lon)
            mapView.addAnnotation(annotation)
//            print(annotation)
        }
    }

Answer 1

Try the following code

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation {
        return nil
    }

    let reuseId = "pin"
    var pinView = mapView.dequeueReusableAnnotationView(withIdentifier: reuseId) as? MKPinAnnotationView
    if pinView == nil {
        pinView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
        pinView?.canShowCallout = true

        let rightButton: AnyObject! = UIButton(type: UIButton.ButtonType.detailDisclosure)
        pinView?.rightCalloutAccessoryView = rightButton as? UIView
    }
    else {
        pinView?.annotation = annotation
    }

    return pinView
}

Don't forget to set mapView's delegate

mapView.delegate = self