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

问题描述

如果我点击列表中的一个项目（只需切换它），我想更改“点击”的值... 但是这个错误来了：“不能在不可变值上使用变异成员：'item'是一个'let'常量” 我理解正确，我认为但我不知道如何修复那个“项目”不再允许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",Gamemode(id: 3,name: "third example text",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()
                    }
            }
        }
    }
}

解决方法

我不知道这是否是最好的解决方案，但也许是：

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",Gamemode(id: 3,name: "third example text",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 swiftui-list