Firebase I am trying to show data taken from Firestore in my SwiftUI view but I have a problem. I have no problem with pulling data from Firebase. But I cannot show the data as I want. I work with MVVM architecture.
My model is like this:
struct UserProfileModel: Identifiable {
@DocumentID var id : String?
var username : String
var uidFromFirebase : String
var firstName : String
var lastName : String
var email : String
}
ViewModel:
class UserProfileViewModel: ObservableObject {
@Published var user : [UserProfileModel] = []
private var db = Firestore.firestore()
func data(){
db.collection("Users").whereField("uuidFromFirebase", isEqualTo: Auth.auth().currentUser!.uid).addSnapshotListener { (snapshot, error) in
guard let documents = snapshot?.documents else {
print("No Documents")
return
}
self.user = documents.compactMap { queryDocumentSnapshot -> UserProfileModel? in
return try? queryDocumentSnapshot.data(as: UserProfileModel.self)
}
}
}
}
View:
struct MainView: View {
@ObservedObject private var viewModel = UserProfileViewModel()
var body: some View { // -> Error: The compiler is unable to type-check this expression in reasonable time; try breaking up the expression into distinct sub-expressions
VStack{
Text(viewModel.user.username) // -> I want to do this but XCode is giving an error.
// This works but I don't want to do it this way.
List(viewModel.user) { user in
VStack{
Text(user.username)
Text(user.firstName)
Text(user.lastName)
Text(user.email)
Text(user.uidFromFirebase)
}
}
}
}
}
In the videos and articles titled "SwiftUI fetch data from Firebase" that I watched and read, I have always narrated on List and ForEach. But I want to use the data wherever. I shared all my code with you. I want to learn how I can do this.
Looks to me like you really just want to have one user that you're pulling the data for, but you've set up your UserProfileViewModel with an array of users ([UserProfileModel]). There are a number of ways that you could take care of this. Here's one (check the code for inline comments about what is going on):
class UserProfileViewModel: ObservableObject {
@Published var user : UserProfileModel? = nil // now an optional
private var db = Firestore.firestore()
func data(){
db.collection("Users").whereField("uuidFromFirebase", isEqualTo: Auth.auth().currentUser!.uid).addSnapshotListener { (snapshot, error) in
guard let documents = snapshot?.documents else {
print("No Documents")
return
}
self.user = documents.compactMap { queryDocumentSnapshot -> UserProfileModel? in
return try? queryDocumentSnapshot.data(as: UserProfileModel.self)
}.first // Take the first document (since there probably should be only one anyway)
}
}
}
struct MainView: View {
@ObservedObject private var viewModel = UserProfileViewModel()
var body: some View {
VStack {
if let user = viewModel.user { //only display data if the user isn't nil
Text(user.username)
Text(user.firstName)
Text(user.lastName)
Text(user.email)
Text(user.uidFromFirebase)
}
}
}
}
I'd say a more traditional way of handling this might be to store your user profile document Users/uid/ -- that way you can just user document(uid) to find it rather than the whereField query.