Hi, 

Is it possible to combine .order(by:) & .whereField on two different fields in a collection on Firebase and use the .addSnapshotlistener?? It works on load but when I add an item to the list it won’t update the list. When I restart the app then it updates the list…

I find very little to almost no information about this on the internet and I've been stuck with my app for 2 weeks because I can't find a solution for this...

Thank you in advance if anyone finds some time to look into this.

import FirebaseFirestoreSwift
import SwiftUI

struct WorkingTeacherModel: Codable {
    @DocumentID var id: String? // @DocumentID to fetch the identifier from Firestore
    var name: String
    var startTime: String
    var startDate: String
    var establishment: String
    var room: String
}

import FirebaseFirestore
import SwiftUI

class WorkingTeacherViewModel: ObservableObject {

    @Published var workingTeachers = [WorkingTeacherModel]() // Reference to Model
    private var db = Firestore.firestore()

    func searchWorkingTeacher(name: String, teachersArray: [WorkingTeacherModel]) -> Int? {
        return teachersArray.firstIndex { $0.name == name }
    }

    func addData(name: String, establishment: String, room: String) {
        let startTimeFormatter =  DateFormatter()
        let endTimeFormatter =  DateFormatter()
        var startTime: String {
            startTimeFormatter.timeStyle = .medium
            startTimeFormatter.locale = Locale(identifier: "nl_BE")
            return startTimeFormatter.string(from: Date.now)
        }
        var startDate: String {
            endTimeFormatter.dateStyle = .short
            endTimeFormatter.locale = Locale(identifier: "nl_BE")
            return endTimeFormatter.string(from: Date.now)
        }
        do {
            _ = db.collection("WorkingTeachers").addDocument(data: ["name": name, "startTime": startTime, "startDate": startDate, "establishment": establishment, "room": room])
        }
    }

    func fetchDataForWorkingTeacherView(establishment: String) {
        db.collection("WorkingTeachers")
            .whereField("establishment", isEqualTo: establishment)
            .order(by: "startTime", descending: true)
            .addSnapshotListener { (querySnapshot, error) in
                guard let documents = querySnapshot?.documents else {
                    print("No documents")
                    return
                }
                self.workingTeachers = documents.compactMap { queryDocumentSnapshot -> WorkingTeacherModel? in
                    return try? queryDocumentSnapshot.data(as: WorkingTeacherModel.self)
                }
            }
    }
}

import FirebaseFirestore
import SwiftUI

struct WorkingTeacherView: View {
    @ObservedObject private var savedEstablishmentViewModel = SavedEstablishmentViewModel()
    @ObservedObject private var workingTeacherViewModel = WorkingTeacherViewModel()
    @ObservedObject private var savedTeacherViewModel = SavedTeacherViewModel()

    var body: some View {
        VStack {
            Text("Vandaag aanwezig in\n\(savedEstablishmentViewModel.establishmentName)")
            NavigationStack {
                VStack {
                    HStack {
                        List {
                            ForEach(workingTeacherViewModel.workingTeachers, id: \.id) { workingTeacher in
                                //WorkingTeacherRowView(workingTeacher: workingTeacher)
                                HStack {
                                    Text(workingTeacher.name)
                                    Spacer()
                                    Text(workingTeacher.startTime)
                                }
                            }
                            .listStyle(.plain)
                        }
                    }
                }
            }
        }
        .onAppear() {
            workingTeacherViewModel.fetchDataForWorkingTeacherView(establishment: savedEstablishmentViewModel.establishmentName)
        }
    }

Best Regards, Brecht

Ok, I needed to create a composite index but I didn't see the message (link) in the console to create the index. Now it works as expected 😊