How do I implement code to make an annotation in MapKit draggable in Swift for iOS?

Question

According to this documentation https://developer.apple.com/documentation/mapkit/mkannotationview/1452401-isdraggable if I set an annotation as draggable, I must also implement setCoordinate.

According to this documentation, https://developer.apple.com/documentation/mapkit/mkannotation/1429528-setcoordinate if I implement setCoordinate I must do so in a key-value observing compliant way.

Have any of you experience with this? Would you show me how this is done? How do you make setCoordinate key-value observing compliant? I'm using Swift for iOS.

Answer 1

I found out from https://forums.developer.apple.com/message/286897?et=watches.email.thread#286897 that I can add the @objc keyword to the class declaration and add @objc and "dynamic" to property "coordinate" and my Swift code becomes key-value observing compliant.