MapViewSwiftUI.swift

struct ContentView: View {
    @State var selectedAnnotation: MKAnnotationID?
    @State var annotations: [MKAnnotation] = []
    
    var body: some View {
        ZStack {
            MapView(selected: self.$selectedAnnotation, annotations: self.$annotations)
            ForEach(self.annotations) { annotation in
                NavigationLink(
                    destination: AnnotationDetailsView(annotation: annotation),
                    tag: annotation.id,
                    selection: self.$selectedAnnotation) {
                        EmptyView()
                    })
            }
        }
    }
}

struct MapView: UIViewRepresentable {
    let selected: Binding<MKAnnotation.ID>
    let annotations: Binding<[MKAnnotation]>
    ...
    func didSelectAnnotation(annotation: MKAnnotation) {
        self.selected.wrappedValue = annotation.id
    }
}