SwiftUI List -> ForEach -> Item 是一个 let，所以我不能改变一个值

Question

如果我点击列表中的某个项目（只需切换它），我想更改“已点击”的值... 但是这个错误来了：“不能在不可变值上使用可变成员：'item' 是一个 'let' 常量” 我认为我的理解是正确的，但我不知道如何修复该“项目”不再允许了即使我在结构中创建一个变异函数来改变值也不起作用

感谢您的帮助！

struct Gamemode: Identifiable {
    var id: Int
    var name: String
    var clicked: Bool
}

struct ContentView: View {
    
    @State private var gamemodes: [Gamemode] = [
        Gamemode(id: 1, name: "example text", clicked: false),
        Gamemode(id: 2, name: "second example text", clicked: false),
        Gamemode(id: 3, name: "third example text", clicked: false),
        Gamemode(id: 4, name: "fourth example text", clicked: false)
    ]
    
    
    
    var body: some View {
        List {
            ForEach(gamemodes) { item in
                    VStack {
                        Text("Selection \(item.id)")
                        Text("\(item.name)")
                    }
                    .background(Color((item.clicked) ? .blue : .yellow))
                    .onTapGesture {
                        item.clicked.toggle()
                    }
            }
        }
    }
}

Answer 1

我不知道这是否是最好的解决方案，但也许是这样：

import SwiftUI

struct Gamemode: Identifiable {
    var id: Int
    var name: String
    var clicked: Bool
}

struct ContentView: View {

    @State private var gamemodes: [Gamemode] = [
        Gamemode(id: 1, name: "example text", clicked: false),
        Gamemode(id: 2, name: "second example text", clicked: false),
        Gamemode(id: 3, name: "third example text", clicked: false),
        Gamemode(id: 4, name: "fourth example text", clicked: false)
    ]



    var body: some View {
        List {
            ForEach(0..<gamemodes.count) { index in
                    VStack {
                        Text("Selection \(gamemodes[index].id)")
                        Text("\(gamemodes[index].name)")
                    }
                    .background(Color((gamemodes[index].clicked) ? .blue : .yellow))
                    .onTapGesture {
                        gamemodes[index].clicked.toggle()
                    }
            }
        }
    }
}

SwiftUI List -> ForEach -> Item 是一个 let，所以我不能改变一个值

SwiftUI List -> ForEach -> Item is a let, so i can't change a value

swiftui

swiftui-list