带自定义ID的动态Picker实现问题：无法获取选中项ID

问题核心在于你当前仅使用了字符串数组存储名称，丢失了对应的ID关联信息。只需直接使用解码后的[UnnamedDeck]模型数组构建Picker，即可同时实现名称展示与ID获取。

1. 调整View的数据存储与异步加载逻辑 #

在你的View中，直接存储完整的UnnamedDeck数组，并绑定选中的模型（或ID）：

struct YourDeckPickerView: View {
    @State private var unnamedDecks: [UnnamedDeck] = []
    @State private var selectedDeck: UnnamedDeck? // 绑定整个模型，便于获取所有字段

    var body: some View {
        Picker("选择卡组", selection: $selectedDeck) {
            // 用UnnamedDeck数组构建选项，指定唯一标识为ID
            ForEach(unnamedDecks, id: \.ID) { deck in
                Text(deck.name)
            }
        }
        // 异步加载数据
        .task {
            if let deckList = await getUnnamedDecksList() {
                self.unnamedDecks = deckList.decks
                // 可选：设置默认选中第一个选项
                self.selectedDeck = deckList.decks.first
            }
        }
        // 监听选中变化，获取ID
        .onChange(of: selectedDeck) { newSelectedDeck in
            if let deckID = newSelectedDeck?.ID {
                print("当前选中的卡组ID：\(deckID)")
                // 在这里处理ID的后续业务逻辑
            }
        }
    }
}

2. 可选：仅绑定ID字符串 #

如果不需要完整模型，仅需获取ID，可修改为绑定字符串类型的ID：

struct YourDeckPickerView: View {
    @State private var unnamedDecks: [UnnamedDeck] = []
    @State private var selectedDeckID: String = ""

    var body: some View {
        Picker("选择卡组", selection: $selectedDeckID) {
            ForEach(unnamedDecks, id: \.ID) { deck in
                // 给每个选项标记对应的ID
                Text(deck.name).tag(deck.ID)
            }
        }
        .task {
            if let deckList = await getUnnamedDecksList() {
                self.unnamedDecks = deckList.decks
                self.selectedDeckID = deckList.decks.first?.ID ?? ""
            }
        }
        .onChange(of: selectedDeckID) { id in
            print("当前选中的卡组ID：\(id)")
        }
    }
}

3. 修复数据获取函数的冗余操作 #

你的getUnnamedDecksList中存在不必要的Data转String再转回Data的操作，直接用原始Data解码即可：

func getUnnamedDecksList() async -> UnnamedDeckList? {
    let downloadTask = Task { () -> UnnamedDeckList in
        let url : String = "****"
        
        var components = URLComponents(string: url)!
        components.queryItems = [
            URLQueryItem(name: "action", value: "unnamedDecks")
        ]
        components.percentEncodedQuery = components.percentEncodedQuery?.replacingOccurrences(of: "+", with: "%2B")
        let (data, _) = try await URLSession.shared.data(from: components.url!)
        // 直接使用原始Data解码，去掉冗余转换步骤
        return try JSONDecoder().decode(UnnamedDeckList.self, from: data)
    }
    let result = await downloadTask.result
    do {
        return try result.get()
    } catch {
        print("数据获取失败：\(error)")
        return nil
    }
}

内容的提问来源于stack exchange，提问作者Ceri Turner