SwiftUI弹出窗口在NavigationView内时消失

struct CustomNavigationView<Content: View>: View {
    let content: Content
    
    init(@ViewBuilder content: () -> Content) {
        self.content = content()
    }
    
    var body: some View {
        #if os(iOS)
        NavigationView {
            content
        }
        #else
        content
        #endif
    }
}

struct ContentView: View {
    @State private var isShowingPopup = false
    
    var body: some View {
        CustomNavigationView {
            VStack {
                Text("Hello, World!")
                    .padding()
                
                Button("Show Popup") {
                    isShowingPopup = true
                }
                .padding()
                .sheet(isPresented: $isShowingPopup) {
                    PopupView()
                }
            }
        }
    }
}

struct PopupView: View {
    @Environment(\.presentationMode) var presentationMode
    
    var body: some View {
        VStack {
            Text("Popup Content")
                .padding()
            
            Button("Close") {
                presentationMode.wrappedValue.dismiss()
            }
            .padding()
        }
    }
}