Observing Firebase Authenfication with ObservableObject - firebase-authentication

Question

I am trying to observe firebase authentification and update my View accordingly.
I have an SessionStore object:
class SessionStore: ObservableObject {
#Published var session: Account?
var handle: AuthStateDidChangeListenerHandle?
deinit {
stopListen()
}
func listen() {
if handle == nil {
handle = Auth.auth().addStateDidChangeListener { (auth, user) in
if let user = user {
print("User logged in: \(user)")
self.session = Account.preData
} else {
self.session = nil
}
}
}
}
func stopListen() {
if let handle = handle {
Auth.auth().removeStateDidChangeListener(handle)
}
}
}
I use it in a view like this:
struct TabBarView: View {
#EnvironmentObject var sessionStore: SessionStore
#State var selectedTab = Tab.swiping
enum Tab: Int {
case swiping, matches, profil
}
func getUser() {
sessionStore.listen()
}
var body: some View {
Group {
if (sessionStore.session != nil) {
TabView(selection: $selectedTab) {
SwipingView().tabItem {
TabBarItem(text: "Text", image: "pause.circle")
}.tag(Tab.swiping)
}
} else {
LoginView()
}
}.onAppear(perform: getUser).onDisappear(perform: sessionStore.stopListen)
}
}
And call it like this:
sessionStore = SessionStore()
TabBarView().environmentObject(sessionStore!)
But it is only showing the LoginView even when the session is not nil. I made some code changes this is actually the solution.

Answer 1

I think this is the way to do that
class SessionStore: ObservableObject {
#Published var session: Account?
Also you referenced self inside the state closure meaning your object will never deinit. Add unowned or weak like so:
handle = Auth.auth().addStateDidChangeListener { [unowned self] (auth, user) in
https://www.avanderlee.com/swift/weak-self/

Answer 2

The correct implementation is:
class SessionStore: ObservableObject {
let objectWillChange = ObservableObjectPublisher()
var session: Account? {
didSet {
objectWillChange.send()
}
}
var handle: AuthStateDidChangeListenerHandle?
deinit {
stopListen()
}
func listen() {
handle = Auth.auth().addStateDidChangeListener { (auth, user) in
if let user = user {
print("User logged in: \(user)")
self.session = Account.preData
} else {
self.session = nil
}
}
}
func stopListen() {
if let handle = handle {
Auth.auth().removeStateDidChangeListener(handle)
}
}
}
More info about it:
https://www.pointfree.co/blog/posts/30-swiftui-and-state-management-corrections