Swift Xcode 12、New Project、App、Use Core Dataのコードがいけていない?

デフォルトのコード

:
:
:
struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @FetchRequest(
        sortDescriptors: [NSSortDescriptor(keyPath: \Item.timestamp, ascending: true)],
        animation: .default)
    private var items: FetchedResults<Item>

    var body: some View {
        List {
            ForEach(items) { item in
                Text("Item at \(item.timestamp!, formatter: itemFormatter)")
            }
            .onDelete(perform: deleteItems)
        }
        .toolbar {
            #if os(iOS)
            EditButton()
            #endif

            Button(action: addItem) {
                Label("Add Item", systemImage: "plus")
            }
        }
    }
:
:
:

リストは表示されるが、「.toolbar」は?
NavigationViewが必要では?

NavigationView追加

:
:
:
struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @FetchRequest(
        sortDescriptors: [NSSortDescriptor(keyPath: \Item.timestamp, ascending: true)],
        animation: .default)
    private var items: FetchedResults<Item>

    var body: some View {
        NavigationView {
            List {
                ForEach(items) { item in
                    Text("Item at \(item.timestamp!, formatter: itemFormatter)")
                }
                .onDelete(perform: deleteItems)
            }
            .toolbar {
                #if os(iOS)
                EditButton()
                #endif

                Button(action: addItem) {
                    Label("Add Item", systemImage: "plus")
                }
            }
        }
    }
:
:
:

AddItemはまだ表示されないか。。。

toolbar内をHStackにする

:
:
:
struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @FetchRequest(
        sortDescriptors: [NSSortDescriptor(keyPath: \Item.timestamp, ascending: true)],
        animation: .default)
    private var items: FetchedResults<Item>

    var body: some View {
        NavigationView {
            List {
                ForEach(items) { item in
                    Text("Item at \(item.timestamp!, formatter: itemFormatter)")
                }
                .onDelete(perform: deleteItems)
            }
            .toolbar {
                HStack {
                    #if os(iOS)
                    EditButton()
                    #endif

                    Button(action: addItem) {
                        Label("Add Item", systemImage: "plus")
                    }
                }
            }
        }
    }
:
:
:

Swift

Posted by shi-n