NavigationStack

swift

struct ContentView: View {
	@State private var openSheet: Bool = false
	
	var body: some View {
		NavigationStack {
			VStack {
				...
			}
			.navigationBarTitle("title ..")
			.toolbar {
				ToolbarItem(placement: .navigationBarTrailing) {
					Button("Open") {
						openSheet = true
					}
				}
			}
			.sheet(isPresented: $openSheet) {
				ChildView(openSheet: $openSheet)
			}
		}
	}
}

ヘッダを表示しない

swift

// こう書く
.toolbar(.hidden, for: .navigationBar)

// 古い書き方
.navigationBarHidden(true) // deprecated