SwiftUI-前提条件失败：无效的输入索引：键盘通知上为4

Question

仅在模拟器上测试。我发现在显示键盘时可以滚动VStack的一些代码

但我收到错误消息precondition failure: invalid input index: 4附加了图片

我也上传了video。

import SwiftUI
import Combine

struct AdaptsToKeyboard: ViewModifier {
    @State var currentHeight: CGFloat = 0

    func body(content: Content) -> some View {
        GeometryReader { geometry in
            content
                .padding(.bottom, self.currentHeight)
                .animation(.easeOut(duration: 0.16))
                .onAppear(perform: {
                    NotificationCenter.Publisher(center: NotificationCenter.default, name: UIResponder.keyboardWillShowNotification)
                        .merge(with: NotificationCenter.Publisher(center: NotificationCenter.default, name: UIResponder.keyboardWillChangeFrameNotification))
                        .compactMap { notification in
                            notification.userInfo?["UIKeyboardFrameEndUserInfoKey"] as? CGRect
                    }
                    .map { rect in
                        rect.height - geometry.safeAreaInsets.bottom
                    }
                    .subscribe(Subscribers.Assign(object: self, keyPath: \.currentHeight))

                    NotificationCenter.Publisher(center: NotificationCenter.default, name: UIResponder.keyboardWillHideNotification)
                        .compactMap { notification in
                            CGFloat.zero
                    }
                    .subscribe(Subscribers.Assign(object: self, keyPath: \.currentHeight))
                })
        }
    }
}

这是我使用此修饰符的方式：

struct LoginView: View {

    @State private var email = ""
    @State var showWelcomeView = false
    @State var loopAnimation = false

    var body: some View {
        NavigationView {
            ZStack {
                Color.customLightGray
                if self.loopAnimation {
                    VStack {
                        LottieView(named: "19451-blue-preloader",
                                   loop: self.loopAnimation,
                                   size: 200
                        ).padding(.top, 350)
                            .padding(.leading, 110)

                    }.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .topLeading)
                } else {
                    VStack (alignment: .leading, spacing: 10) {
                        Text("Email:")
                            .font(.headline)

                        TextField("Enter your email", text: $email)
                            .padding(.all)
                            .font(Font.system(size: 18, weight: .medium, design: .rounded))
                            .overlay(RoundedRectangle(cornerRadius: 8).stroke(Color.blue, lineWidth: 1))
                            .foregroundColor(Color.blue)
                            .keyboardType(.emailAddress)
                            .autocapitalization(.none)

                        Button(action: {
                        }) {
                            Text("Forgot password?")
                                .fontWeight(.bold)
                                .font(.headline)
                                .padding(EdgeInsets(top: 20, leading: 10, bottom: 20, trailing: 0))
                                .foregroundColor(.blue)
                        }

                        HStack {
                            Button(action: {
                            }) {
                                Text("Create account")
                                    .fontWeight(.bold)
                                    .font(.subheadline)
                                    .padding()
                                    .foregroundColor(.blue)
                            }

                            Spacer()

                            Button(action: {
                                self.loopAnimation.toggle()
                                self.fetchUser(with: self.email)
                            }) {
                                Text("Next")
                                    .fontWeight(.bold)
                                    .font(.title)
                                    .padding(EdgeInsets(top: 20, leading: 40, bottom: 20, trailing: 40))
                                    .background(Color.blue)
                                    .cornerRadius(8)
                                    .foregroundColor(.white)
                            }

                            NavigationLink(destination: WelcomeView(), isActive: $showWelcomeView) { EmptyView() }
                        }

                    }.padding(.horizontal, 30)
                        .modifier(AdaptsToKeyboard())
                }

            }
            .navigationBarTitle(Text("Login"))
            .edgesIgnoringSafeArea(.all)
        }
    }

    func fetchUser(with email: String) {

        UserService().getUser(with: email) { (user) in
            self.loopAnimation = false
            self.showWelcomeView = true
        }

    }
}

struct LoginView_Previews: PreviewProvider {
    static var previews: some View {
        LoginView()
    }
}

如果我删除了if self.loopAnimation条件，那么我的代码在没有这种SIGABRT的情况下会很好地工作