Updates To Firebase Firestore Document Popping View Off Navigation Stack SwiftUI - firebase

Question

I am working on a SwiftUI app and using Firebase Firestore as a backend. I am noticing an odd behavior when I update a document in Firestore that results in a view being popped off the Navigation stack each time a field is updated. The Navigation Stack is as follows.
MarketplaceView with List Containing ListingRowViews
Tapping a row takes you to a ListingDetailView.
Tapping a Buy Now button in ListingDetailView takes you to a ConfirmationView.
When updates are made to the document and 1 or 2 is present, the view updates and all behaves as expected. When 3 (ConfirmationView) is present, any updates to the document result in the ConfirmationView being popped off the stack back to 2 the ListingDetailView. Below is the app architecture.
ListingRepository - Creates a snapshotListener for all Listings in Firestore.
class ListingRepository: ObservableObject {
let db = Firestore.firestore()
private var snapshotListener: ListenerRegistration?
#Published var listings = [Listing]()
private var cancellables = Set<AnyCancellable>()
init() {
startSnapshotListener()
}
func startSnapshotListener() {
// Add a SnapshotListener to the Listing Collection.
self.snapshotListener = db.collection(FirestoreCollection.listings).addSnapshotListener { (querySnapshot, error) in
if let error = error {
print("Error getting documents: \(error)")
} else {
// Check to make sure the Collection contains Documents
guard let documents = querySnapshot?.documents else {
print("No Listings.")
return
}
// Documents exist.
self.listings = documents.compactMap { listing in
do {
return try listing.data(as: Listing.self)
} catch {
print(error)
}
return nil
}
}
}
}
}
MarketplaceViewModel - Subscribes to Listings from ListingRepository and creates ListingRowViewModels.
class MarketplaceViewModel: ObservableObject {
// Properties
#Published var listingRepository: ListingRepository = Resolver.resolve()
// Published Properties
#Published var listingRowViewModels = [ListingRowViewModel]()
// Combine Cancellable
private var cancellables = Set<AnyCancellable>()
// Intitalizer
init() {
self.startCombine()
}
// Starting Combine
func startCombine() {
listingRepository
.$listings
.receive(on: RunLoop.main)
.map { listings in
listings
.map { listing in
ListingRowViewModel(listing: listing)
}
}
.assign(to: \.listingRowViewModels, on: self)
.store(in: &cancellables)
}
}
MarketplaceView - Creates the List full of ListingDetailViews
struct MarketplaceView: View {
#ObservedObject var marketplaceViewModel: MarketplaceViewModel = Resolver.resolve()
var body: some View {
return NavigationView {
List {
ForEach(self.marketplaceViewModel.listingRowViewModels, id: \.id) { listingRowViewModel in
NavigationLink(destination: ListingDetailView(listingDetailViewModel: ListingDetailViewModel(listing: listingRowViewModel.listing))
) {
ListingRowView(listingRowViewModel: listingRowViewModel)
}
} // ForEach
.navigationTitle("Marketplace")
} // NavigationView
} // View
}
}
ListingRowViewModel - View model for each row.
class ListingRowViewModel: ObservableObject, Identifiable {
// Properties
var id: String = ""
// Published Properties
#Published var listing: Listing
// Combine Cancellable
private var cancellables = Set<AnyCancellable>()
// Initializer
init(listing: Listing) {
self.listing = listing
self.startCombine()
}
// Starting Combine
func startCombine() {
$listing
.receive(on: RunLoop.main)
.compactMap { listing in
listing.id
}
.assign(to: \.id, on: self)
.store(in: &cancellables)
}
}
ListingRowView - View for each row.
struct ListingRowView: View {
#ObservedObject var listingRowViewModel: ListingRowViewModel
var body: some View {
Text(self.listingRowViewModel.listingId)
} // View
}
ListingDetailViewModel - View model for the detail view.
class ListingDetailViewModel: ObservableObject, Identifiable {
var listing: Listing
// Initializer
init(listing: Listing) {
self.listing = listing
}
}
ListingDetailView - Detail View For Listing
struct ListingDetailView: View {
var listingDetailViewModel: ListingDetailViewModel
var body: some View {
VStack {
Text(self.listingDetailViewModel.listing.id)
NavigationLink(destination: ConfirmationView(confirmationViewModel: ConfirmationViewModel(listing: listing))) {
Text("Buy Now")
}
}
.navigationTitle("Listing Info")
} // View
}
ConfirmationViewModel - View model for Confirmation View
class ConfirmationlViewModel: ObservableObject, Identifiable {
var listing: Listing
// Initializer
init(listing: Listing) {
self.listing = listing
}
}
ConfirmationView - Confirmation View
struct ConfirmationView: View {
var confirmationViewModel: ConfirmationViewModel
var body: some View {
VStack {
Text(self.confirmationViewModel.listing.id)
Button(action: {
self.confirm()
}, label: {
Text("Confirm")})
}
.navigationTitle("Order Confirmation")
} // View
}
Any help would be greatly appreciated.