Swift SwiftUI-scrollview错误？错误：编译器无法在合理的时间对该表达式进行类型检查；尝试分手

问题描述

我真的在这里迷路了。这是我的错误还是XCode的错误？这是关于带有List的ContentView的，用户可以按一个按钮跳转到带有相应字母的名称。我遇到两个问题，一个是上面的错误，第二个是，如果ClientData更改了列表顶部的索引按钮，则应该对其进行更新。首先，我想在.onappear中执行此操作，但随后，像现在一样，我只获得名称的第一字母，这些字母在屏幕上可见。因此，当我对Client Array排序以收集firstLetter时，我喜欢构建列表。

import SwiftUI
import PlaygroundSupport
import Combine

struct ClientModel : Identifiable,Hashable {
    var id : Int
    var firstName : String
    var lastName : String
}

class ClientData : ObservableObject   {
 @Published var clients : [ClientModel] = [
    ClientModel(id: 1,firstName: "jan",lastName: "Pieters"),ClientModel(id: 2,firstName: "kees",lastName: "Jansen"),ClientModel(id: 3,firstName: "jaap",ClientModel(id: 66,firstName: "koos",lastName: "Werkeloos")
 ]
}


struct ContentView: View {
 @Observedobject var clients = ClientData()
 @State private var indexDict : Dictionary<String,Int> = [:]


 var body: some View {
    ScrollViewReader { scrollProxy in
        vstack {
            HStack {
                ForEach ( indexDict.sorted(by: { (lhs,rhs) -> Bool in
                                            lhs.key < rhs.key}),id: \.key ) { key,value in
                    Button {
                        withAnimation {
                            scrollProxy.scrollTo(value,anchor: .top)
                        }
                    }.buttonStyle(SectionIndexButtonStyle())
                }
            }
            ScrollView {
                Lazyvstack {
                    ForEach( clients.clients.sorted(by: { (lhs,rhs) -> Bool in
                                                        lhs.lastName! < rhs.lastName!}),id: \.id ) { client in
                        buildindex(proxy: scrollProxy,item: client)
                        RowView(text: (client.lastName! + "," + client.firstName! + "," + "\(client.id)" ) as String )
                            .onAppear( print(client.lastName!) )
                            .id( client.id )
                    }
                }
            }
        }
    }
    .navigationTitle("Clients")
 }

 func buildindex(proxy: ScrollViewProxy,item: ClientModel) {
    let firstLetter = item.lastName.trimmingCharacters(in: .whitespaces).prefix(1).uppercased()
    print("firstLetter : \(firstLetter)")

    if indexDict.keys.contains(firstLetter) {
        if indexDict[firstLetter] != nil {
            indexDict[firstLetter] = item.id
            print("did contain the letter but empty id")
        } else {
            print(indexDict[firstLetter] ?? "??")
            print("does contain the letter and id")
        }
    } else {
        print("Not found")
        indexDict[firstLetter] = item.id
        print("does contain Now the letter and id")
    }
 }
}

struct MySubView: View {
 @Binding var contentViewConfig : ContentViewConfig
 var body : some View {
    // ...
    Text("press me")

 }
}

struct RowView: View {
 let text: String

 var body: some View{
    Text(text)
        .padding()
        .frame(maxWidth: .infinity,alignment: .leading )
 }
}

struct SectionIndexButtonStyle: ButtonStyle {
 func makeBody(configuration: Self.Configuration) -> some View {
    configuration.label
        .foregroundColor(configuration.ispressed ? Color.gray.opacity(0.2) : Color.accentColor.opacity(0.1))
        .background(configuration.ispressed ? Color.white : Color.gray.opacity(0.1))
        .cornerRadius(15.0)
        .overlay(RoundedRectangle(cornerRadius: 15.0) .stroke(linewidth: 1.0).foregroundColor(.accentColor))
        .padding(0)
 }
}

PlaygroundPage.current.liveView = UIHostingController(rootView:
                                                    ContentView())

我确实注释了几个部分，以检查在哪里可以找到该crillpit，但仍然遇到相同的错误。有什么想法，我怎么能理解这个问题？

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

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