menu - SwiftUI - 如何在表单中添加 "letters sections"和字母跳线？

Question

如何创建一个表单，其中的元素会根据其首字母自动分为多个部分，并在右侧添加字母表跳线以显示以所选字母开头的元素(就像“联系人”应用程序一样)？

我还注意到一个奇怪的事情，我不知道如何重新创建:并非所有字母都显示，其中一些显示为“•”。然而，当你点击它们时，它们无论如何都会带你到相应的字母。我尝试在 ZStack 中使用 ScrollView(.vertical) 并将 .scrollTo(selection) 添加到按钮的操作中，但是 1) 它没有滚动到我想要的选择 2) 当我点击“•”时，就好像我正在点击所有这些因为他们都做了点击动画 3) 我无法按照我的意愿划分列表。 我有这个:

import SwiftUI

struct ContentView: View {

let alphabet = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W", "X","Y", "Z"]
let values = ["Avalue", "Bvalue", "Cvalue", "Dvalue"]

var body: some View {
           ScrollViewReader{ scrollviewr in
               ZStack {
                   ScrollView(.vertical) {
                       VStack {
                           ForEach(alphabet, id: \.self) { letters in
                               Button(letters){
                                   withAnimation {
                                    scrollviewr.scrollTo(letters)
                                   }
                               }
                           }
                       }
                   }.offset(x: 180, y: 120)

                VStack {
                    
                ForEach(values, id: \.self){ vals in
                               Text(vals).id(vals)
                   }
                }
               }
           }
   }
}

但我想要这样:

Answer 1

import SwiftUI

struct AlphabetSort2: View {
    let alphabet = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W", "X","Y", "Z"]
    let values = ["Avalue", "Bvalue", "Cvalue", "Dvalue", "Mvalue", "Zvalue"]
    var body: some View {
        ScrollView {
            ScrollViewReader { value in
                ZStack{
                    List{
                        ForEach(alphabet, id: \.self) { letter in
                            Section(header: Text(letter)) {
                                ForEach(values.filter { $0.hasPrefix(letter) }, id: \.self) { vals in
                                    Text(vals).id(vals)
                                }
                            }.id(letter)
                        }
                    }
                    HStack{
                        Spacer()
                        VStack {
                            ForEach(0..<alphabet.count, id: \.self) { idx in
                                Button(action: {
                                    withAnimation {
                                        value.scrollTo(alphabet[idx])
                                    }
                                }, label: {
                                    Text(idx % 2 == 0 ? alphabet[idx] : "\u{2022}")
                                })
                            }
                        }
                    }
                }
            }
        }
    }
}

struct AlphabetSort2_Previews: PreviewProvider {
    static var previews: some View {
        AlphabetSort2()
    }
}