SwiftUI中HomeList与SampleDataList间导航失败问题求助

开发测试项目，目标实现从HomeList导航到SampleDataList，再根据URL文件类型跳转至不同视图，不使用Master/Detail模式。

运行代码时出现以下错误：

Note: Links search for destinations in any surrounding NavigationStack, then within the same column of a NavigationSplitView. A NavigationLink is presenting a value of type "URL" but there is no matching navigationDestination declaration visible from the location of the link. The link cannot be activated.

已尝试以下方案但均无效：

• 将navigationDestination(for:destination:)移至HomeList中
• 将SampleDataList嵌入NavigationStack
• 使用NavigationPath（操作可能有误，未生效）

原代码 #

struct HomeList: View {
    
    var body: some View {
        NavigationStack {
            List {
                NavigationLink {
                    SampleDataList()
                } label: {
                    Text("Sample Data Picker")
                }
            }
        }
    }
}

extension URL: Identifiable {
    
    public var id: Int { self.hashValue }
    
}

struct SampleDataList: View {
    
    var urls: [URL] {
        let path = Bundle.main.resourcePath!
        let url = URL(fileURLWithPath: path).appendingPathComponent("SampleData")
        return try! FileManager.default.contentsOfDirectory(at: url, includingPropertiesForKeys: nil)
    }
    
    var body: some View {
        List(urls) { url in
            NavigationLink(value: url) {
                Text("\(url.lastPathComponent)")
            }
        }
        .listStyle(PlainListStyle())
        .navigationDestination(for: URL.self) { url in
            Text("\(url.lastPathComponent)")
        }
    }
}

问题核心是导航目的地的作用域不匹配：使用value参数的NavigationLink需要对应的navigationDestination声明在其所在的顶层NavigationStack范围内，否则链路无法识别跳转目标。

修正方案（推荐） #

将navigationDestination(for: URL.self)移至顶层NavigationStack内部，确保整个导航栈能识别URL类型的跳转：

struct HomeList: View {
    var body: some View {
        NavigationStack {
            List {
                NavigationLink {
                    SampleDataList()
                } label: {
                    Text("Sample Data Picker")
                }
            }
            // 将导航目的地声明放在顶层NavigationStack内
            .navigationDestination(for: URL.self) { url in
                Text("\(url.lastPathComponent)")
            }
        }
    }
}

extension URL: Identifiable {
    // 替换hashValue为absoluteString，避免ID碰撞风险
    public var id: String { self.absoluteString }
}

struct SampleDataList: View {
    var urls: [URL] {
        let path = Bundle.main.resourcePath!
        let url = URL(fileURLWithPath: path).appendingPathComponent("SampleData")
        return try! FileManager.default.contentsOfDirectory(at: url, includingPropertiesForKeys: nil)
    }
    
    var body: some View {
        List(urls) { url in
            NavigationLink(value: url) {
                Text("\(url.lastPathComponent)")
            }
        }
        .listStyle(PlainListStyle())
        // 移除此处的navigationDestination
    }
}

补充说明 #

• 原URL的Identifiable扩展用hashValue作为id存在碰撞风险，改用absoluteString能保证ID唯一。
• 若坚持在SampleDataList内声明navigationDestination，需给SampleDataList单独嵌套NavigationStack，但这种方式会形成嵌套导航栈，仅在特定场景下适用。

内容的提问来源于stack exchange，提问作者DanubePM