用SwiftUI处理CoreData中标题/细节视图的正确方法

import SwiftUI
import CoreData

struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext
    @FetchRequest(sortDescriptors: [NSSortDescriptor(keyPath: \Item.timestamp, ascending: true)])
    private var items: FetchedResults<Item>

    var body: some View {
        NavigationView {
            List {
                ForEach(items) { item in
                    NavigationLink(destination: DetailView(item: item)) {
                        Text(item.title ?? "")
                    }
                }
            }
            .navigationBarTitle("Items")
        }
    }
}

struct DetailView: View {
    @ObservedObject var item: Item

    var body: some View {
        VStack {
            Text(item.title ?? "")
                .font(.title)
            Text(item.detail ?? "")
                .font(.body)
        }
        .padding()
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView().environment(\.managedObjectContext, PersistenceController.preview.container.viewContext)
    }
}