Select MKMarkerAnnotationView with custom callout after adding annotation - swift

Question

I have an MKMapView on which I would like to add annotations on a long press gesture. After adding the annotation, I would like to select the annotation view. Quite a simple request I assumed.
The problem is that I am using the new MKMarkerAnnotationView with a custom rightCalloutAccessoryView and a custom detailCalloutAccessoryView. It is not very well documented yet, but the WWDC 2017 Session 237 states that the callout will be displayed when there is more than a title/subtitle.
Unfortunately, this is not the case for me. When I programmatically (and manually) select the annotation, I get a weird double selected state where I can see the callout AND the marker:
Here is the annotation view code:
import Foundation
import MapKit
#available(iOS 11.0, *)
protocol TemporaryUserAnnotationViewDelegate: class {
func temporaryUserAnnotationViewDidTapOk(title: String?, userAnnotationView: TemporaryUserAnnotationView)
}
#available(iOS 11.0, *)
class TemporaryUserAnnotationView: MKMarkerAnnotationView {
weak var delegate: TemporaryUserAnnotationViewDelegate?
var textField: UITextField!
init(annotation: TemporaryUserAnnotation) {
super.init(annotation: annotation, reuseIdentifier: TemporaryUserAnnotationMarkerAnnotationView.reuseIdentifier)
markerTintColor = .lbc_blue
canShowCallout = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func configure(annotation: TemporaryUserAnnotation) {
let detailView = UIView()
detailView.translatesAutoresizingMaskIntoConstraints = false
textField = UITextField()
textField.translatesAutoresizingMaskIntoConstraints = false
textField.placeholder = "Titre"
detailView.addSubview(textField)
detailView.heightAnchor.constraint(equalToConstant: 21).isActive = true
detailView.widthAnchor.constraint(equalToConstant: 100).isActive = true
textField.centerXAnchor.constraint(equalTo: detailView.centerXAnchor).isActive = true
textField.centerYAnchor.constraint(equalTo: detailView.centerYAnchor).isActive = true
textField.heightAnchor.constraint(equalToConstant: 21).isActive = true
textField.widthAnchor.constraint(equalToConstant: 100).isActive = true
detailCalloutAccessoryView = detailView
let rightView = UIView(frame: CGRect(origin: .zero, size: CGSize(width: 50, height: 70)))
rightView.backgroundColor = .lbc_blue
let button = UIButton(frame: CGRect(origin: .zero, size: CGSize(width: 50, height: 40)))
button.setTitle("OK", for: .normal)
button.setTitleColor(.white, for: .normal)
button.addTarget(self, action: #selector(tapRightCalloutAccessoryViewButton), for: .touchUpInside)
rightView.addSubview(button)
rightCalloutAccessoryView = rightView
}
#objc func tapRightCalloutAccessoryViewButton() {
delegate?.temporaryUserAnnotationViewDidTapOk(title: textField.text, userAnnotationView: self)
}
}
and here is the controller code:
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
print(#function)
if annotation is MKUserLocation { return nil }
if #available(iOS 11.0, *) {
switch annotation {
case let temporarayUserAnnotation as TemporaryUserAnnotation:
if let view = mapView.dequeue() as? TemporaryUserAnnotationView {
view.annotation = annotation
return view
} else {
let view = TemporaryUserAnnotationView(annotation: temporarayUserAnnotation)
view.delegate = self
view.configure(annotation: temporarayUserAnnotation)
return view
}
default:
return nil
}
} else {
let identifier = "marker"
if let view = mapView.dequeueReusableAnnotationView(withIdentifier: identifier) as? MKPinAnnotationView {
view.annotation = annotation
return view
} else {
return MKPinAnnotationView(annotation: annotation, reuseIdentifier: identifier)
}
}
}
I simply add annotations this way:
func addUserAnnotation(coordinate: CLLocationCoordinate2D) {
let annotation = TemporaryUserAnnotation(coordinate: coordinate)
mapView.addAnnotation(annotation)
mapView.selectAnnotation(annotation, animated: true)
}
I also tried to implement the mapView(_:didAdd:) method but the result is even worse with the marker view in front of the callout.
Any help would be very appreciated! Thanks!

Answer 1

I found the following workaround: when you add your annotation, wait a second before programmatically selecting it:
func addUserAnnotation(coordinate: CLLocationCoordinate2D) {
let annotation = TemporaryUserAnnotation(coordinate: coordinate)
mapView.addAnnotation(annotation)
DispatchQueue.main.asyncAfter(wallDeadline: .now() + .seconds(1)) {
self.mapView.selectAnnotation(annotation, animated: true)
}
}
I still think this should not be necessary, so if you have a better solution, feel free to post it here!

Answer 2

I just encountered a similar problem because I had a UITapGestureRecognizer of my own competing with MKMapView's selection gesture recognizer. I created and selected the annotation on the tap event, but because both gesture recognizers were firing, and theirs was firing last, it was deselecting immediately.
My solution was to implement UIGestureRecognizerDelegate and become the delegate of my gesture recognizer, and implement the following:
public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return true
}