Swift using annotation callout to call segue - ios

Question

I am working on an App where you can see some pins/annotations and when you click them they show some information about that place. What I want to do is add a button so when the user clicks the "callout" it activates a segue which will open a new View with more detailed information.
I have my code and functions but it seems to be an error, because when I click the button to run the segue, the App crashes. My code is the following...
class ViewController: UIViewController, MKMapViewDelegate {
#IBOutlet weak var mapView: MKMapView!
var pin = MKPointAnnotation()
override func viewDidLoad() {
super.viewDidLoad()
mapView.delegate = self
mapView.showsUserLocation = true
//Adding information to my Annotation
let pinCoordenadas = CLLocationCoordinate2DMake(25.589339000, -100.257724800)
pin.coordinate = pinCoordenadas
pin.title = "Christus Muguerza"
mapView.addAnnotation(pin)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
if !(annotation is MKPointAnnotation) {
print("Not MKPointAnnotation")
}
var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: "identifier")
if annotationView == nil{
annotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: "identifier")
annotationView!.canShowCallout = true
annotationView!.rightCalloutAccessoryView = UIButton(type: .detailDisclosure)
}
else {
annotationView!.annotation = annotation
}
annotationView!.image = UIImage(named: "curz")
return annotationView
}
var anotacionSeleccionada : MKPointAnnotation!
func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, calloutAccessoryControlTapped control: UIControl) {
if control == view.rightCalloutAccessoryView {
anotacionSeleccionada = view.annotation as? MKPointAnnotation
performSegue(withIdentifier: "vista", sender: self)
}
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let destination = segue.destination as? ViewController {
destination.pin = anotacionSeleccionada
}
}
}
The errors...
I hope you guys can help me out, I would really appreciate your help. Thank you

Answer 1

Your outlet to your mapView seem to be broken, since your program crashes on the first row in viewDidLoad. Do this to solve this issue:
Go to your storyboard
Right click on your map
Remove the outlet/outlets if you have by mistake created more than one
Remove #IBOutlet weak var mapView: MKMapView! from your code
Create a new outlet
Run your code again
The issue was that OP had both the mainView and the detailView connected to the file viewController. I created a new file for OP called DetailController and linked the second viewController and now it´s working.