swift - 使用 SwiftUI 的 macOS 应用程序中的导航视图不稳定

Question

我正在尝试使用 SwiftUI 为 macOS 应用程序创建主/详细视图。目标是在侧栏中选择一个项目并让它相应地更改主视图。我的这个例子的代码如下所示：

import SwiftUI

struct MyMasterView: View {

    let names = ["Homer", "Marge", "Bart", "Lisa"]

    var body: some View {

        List {
            ForEach(names, id: \.self) { name in
                NavigationLink(name, destination: MyDetailView(name: name))
            }
        }
        .frame(width: 150, height: 300)

    }
}

struct MyDetailView: View {

    var name = "Name"

    var body: some View {

        HStack {
            Text("Hello \(name)")
                .font(.largeTitle)
        }
        .frame(width: 450, height: 300)

    }
}

struct ContentView: View {

    var body: some View {

        NavigationView {
            MyMasterView()
            MyDetailView()
        }
        .navigationViewStyle(DoubleColumnNavigationViewStyle())
        .frame(width: 600, height: 300)

    }
}

运行 Mac 应用程序时，侧栏选择可能会变为非活动状态，有时会出现弹出视图而不是更改详细视图。有关该问题的屏幕截图，请参见下文。这是 Mac 上 SwiftUI NavigationView 的一个错误，还是我需要实现一些东西才能使其在 macOS 上工作？

https://youtu.be/BF7m1OszZ5w

标签： swiftmacosswiftui

Answer 1

从 Xcode 11.0 (11A420a) 和 macOS Catalina (19A558d) NavigationView 按预期工作：

import SwiftUI

struct DetailView: View {
    let text: String

    var body: some View {
        Text(text)
            .frame(maxWidth: .infinity, maxHeight: .infinity)
    }
}

struct ContentView: View {
    private let names = ["Homer", "Marge", "Bart", "Lisa"]
    @State private var selection: String?

    var body: some View {
        NavigationView {
            List(selection: $selection) {
                Section(header: Text("The Simpsons")) {
                    ForEach(names, id: \.self) { name in
                        NavigationLink(destination: DetailView(text: name)) {
                            Text(name)
                        }
                    }
                }
            }.listStyle(SidebarListStyle())
            DetailView(text: "Make a selection")
        }
    }
}