포인트는

코드

import SwiftUI

struct Person: Identifiable, Hashable {
    var id = UUID()
    var name: String
    var order: Int
}

struct ContentView: View {
    @State var people = [
        Person(name: "taro", order: 1),
        Person(name: "yuki", order: 0)
    ]
    @State var selectedPerson: Person?
    var body: some View {
        VStack {
            AddButton(people: $people)
            NavigationView {
                List(people.sorted{$0.order < $1.order}, id: \.self, selection: $selectedPerson) { person in
                    Text(person.name)
                }.frame(width: 150)
                if selectedPerson != nil {
                    Detail(person: selectedPerson!)
                }
            }
        }
    }
}

struct AddButton: View {
    @Binding var people: [Person]
    var body: some View {
        Button("add", action: {
            print("add")
            self.people.append(Person(name: "fuga", order: -1))
        })
    }
}

struct Detail: View {
    var person: Person
    var body: some View {
        VStack {
            Text(person.name)
        }.frame(maxWidth: .infinity, maxHeight: .infinity)
    }
}