Ios 拖动手势导致 sim 崩溃 Swift UI

您好，我正在try 实现一个拖拽手势的下拉视图，以关闭它.当我向上执行拖动手势时，视图移动了一会儿，然后冻结，整个模拟器冻结，然后Xcode崩溃.例如，当我在刷卡视图上try 这个完全相同的代码时，它起作用了.为什么它在这种情况下不起作用？

import SwiftUI

struct MessagesHomeView: View {
    @State private var offset = CGSize.zero
    
    @State var showNotifications: Bool = false
        
    var body: some View {
        VStack {
            Button {
                withAnimation(.easeInOut){
                    showNotifications.toggle()
                }
            } label: {
                Image(systemName: "bell").font(.title)
            }
        }
        .overlay {
            VStack {
                if showNotifications {
                    ZStack {
                        Color(UIColor.darkGray)
                        VStack(alignment: .leading){
                            Text("Notifications").font(.title3).foregroundColor(.white)
                            Spacer()
                        }.padding(10).padding(.top, 70)
                        VStack {
                            Spacer()
                            RoundedRectangle(cornerRadius: 10).frame(width: 90, height: 9).foregroundColor(.white)
                                .gesture (
                                    DragGesture()
                                        .onChanged { gesture in
                                            if gesture.translation.height < 0 {
                                                offset = gesture.translation
                                            }
                                        }.onEnded { _ in
                                            withAnimation{
                                                modifyState()
                                            }
                                        }

                                )
                        }.padding(.bottom, 4)
                    }
                    .frame(height: 500)
                    .transition(AnyTransition.move(edge: .top).combined(with: .opacity))
                    .cornerRadius(10, corners: [.bottomLeft, .bottomRight])
                    .offset(y: offset.height)
                    Spacer()
                }
            }.ignoresSafeArea()
        }
    }
    func modifyState(){
        switch offset.height {
        case -600...(-100):
            withAnimation(.easeInOut){
                showNotifications = false
            }
            offset = .zero
        default:
            withAnimation(.easeInOut){
                offset = .zero
            }
        }
    }
}