如何在 SwiftUI 中迭代/foreach 數組

Question

我有這個字典數組。

let deckColors = [
    ["name": "blue", "desc": "desc1"],
    ["name": "yellow", "desc": "desc2"],
]

而我的觀點：

struct ContentView: View {
    var body: some View {
        ForEach(0 ..< deckColors.count) {value in
            Text(deckColors[value]["name"])
        }
    }
}

我怎樣才能讓它工作？ 當前收到此錯誤：協議類型Any不能符合StringProtocol因為只有具體類型才能符合協議

Answer 1

這似乎是實現結構體的一種非常復雜的方法：

struct DeckColor {
    var name: String
    var desc: String
}

let deckColors = [
    DeckColor(name: "blue", desc: "desc1"),
    DeckColor(name: "yellow", desc: "desc2")
]

struct ContentView: View {
    var body: some View {
        ForEach(0 ..< deckColors.count) { value in
            Text(deckColors[value].name)
        }
    }
}

您實現它的方式需要處理字典不包含"name"值的情況。 你可以這樣做，但它更丑陋，更脆弱：

struct ContentView: View {
    var body: some View {
        ForEach(0 ..< deckColors.count) { value in
            Text(deckColors[value]["name"] ?? "default text if name isn't there.")
        }
    }
}

Answer 2

這對我有用

struct ContentView: View {
    let deckColors = [
        ["name": "blue", "desc": "desc1"],
        ["name": "yellow", "desc": "desc2"],
    ]

    var body: some View {
        ForEach(0 ..< deckColors.count, id: \.self) {value in
            Text(String(self.deckColors[value]["name"]!))
        }
    }
}

Answer 3

我會將您的套牌顏色放入一個枚舉中，然后對其進行迭代。

enum DeckColor: String, CaseIterable {
    case blue
    case yellow

    var desc: String {
        switch self {
            case .blue: return "desc1"
            case .yellow: return "desc2"
        }
    }
}

struct ContentView: View {
    var body: some View {
        VStack(alignment: .leading) {
            ForEach(DeckColor.allCases, id: \.self) { color in
                Text(color.rawValue)
            }
        }
    }
}