How to access a View Struct in other View struct in swiftui - view

Question

In one view, I have this func to signUp and get userName
func signUp() {
if self.email != "" {
if self.password == self.repass {
session.signUp(email: email, password: password) { (result, error) in
if error != nil {
self.error = error!.localizedDescription
//self.error = "A senha deve ter 6 caracteres ou mais"
}
else{
self.email = ""
self.password = ""
let db = Firestore.firestore()
db.collection("Users").document(result!.user.uid).setData(["userName": userName]) { (error) in
if error != nil{
}
}
}
}
}
else{
self.error = "Senhas não coincidem"
}
}
else{
self.error = "Complete todos espaços"
}
}
In other view, I want to get the userName the user typed ad display it, but for this I need to link both views to get access to func SignUp. How to do it?
EDIT:
Based on the answer I was given, I did the corresponding changes:
SessionStore:
#Published var session: User? = nil
var handle: AuthStateDidChangeListenerHandle?
#Published var userName: String = ""
func listen() {
handle = Auth.auth().addStateDidChangeListener({ [self] (auth, user) in
if let user = user {
self.session = User(uid: user.uid, email: user.email!, userName: userName)
}
else {
self.session = nil
}
})
}
struct User {
var uid:String
var email:String
var userName: String
}
HomeView ----> var userName: User
Text(userName.userName)
explaining how my code works: the #main view is MedAppApp: App. From there, the code goes to ContentView. if session.session != nil, TransitionView, else, SignView. Continuing from SignView, there I have both SignInView and SignUpView views, which they have Button(action: signIn) and Button(action: Signup), respectively. Continuing from TransitionView, there is where I have:
struct TransitionView: View {
#StateObject var LocationModel = LocationViewModel()
#State var userName = User(uid: "", email: "", userName: "")
var body: some View {
HomeView(LocationModel: LocationModel, userName: userName)
}
}
#State var userName =... and userName: userName needed to be added
The app launches, I can signUp with username (and its stored in Firestore with uid as document), but the userName isn't displayed. I think the problem must be in User(uid: "", email: "", password: ""). I didn't know what to add there.
By the way, Im thinking about maintaining the code and then get the userName by using the document id (that already is the user uid) so I can access it. Don't have a final answer yet, but Im working on it.
EDIT2:
I added #StateObject var session = SessionStore()
Tried to use:
#State var userName = User(uid: SessionStore().session?.uid ?? "", email: SessionStore().session?.email ?? "", userName: SessionStore().session?.userName ?? "")
Still doesn't work

Answer 1

Your question is too open-ended, but I'll provide an answer that hopefully will set you up on the right direction.
First, in SwiftUI, separate the concept of a view (i.e. how things are arranged on the screen) from the concept of data that drives the views. What I mean by that is, if you need some data, like userName, the code that obtains it shouldn't know or care about which view will make use of it. And Views, shouldn't care how the data is obtained.
Second, in SwiftUI, views should not be thought of as "entities" (like in UIKit) with their own life cycles. They are just declarative statements that define how the UI is arranged.
For example, suppose you have this (fake) class that signs the user in, and when signed-in, populates the userName property. The instance of this class is a view model.
struct User {
let userName: String
}
class Session: ObservableObject {
#Published var user: User? = nil
func signIn(_ completion: (User) -> ()) {
DispatchQueue.main.asyncAfter(.now() + 0.5) {
self.user = User(userName: "Mateus") // fake sign-in
completion(self.user) // not really used in this example
}
}
}
#Published and ObservableObject in combination are how SwiftUI views know to react to changes to this object. Read more about them, if you don't know what they do.
Next, design a root view that decides what inner view to display depending on whether the user is signed in or not:
struct RootView: View {
#StateObject var session = Session()
var body: some View {
VStack() {
if let user = session.user {
ContentView(user: user) // view is conditionally rendered
} else {
Button("sign in") { self.signIn() }
}
}
}
func signIn() {
self.session.signIn() {
print("signed in...!")
}
}
}
#StateObject manages the life cycle of the view model for the view.
As you see above, ContentView will only be rendered when session.user is not nil (i.e. when user has signed in), so the view is driven by changes in data. I did not need to create a ContentView instance anywhere ahead of time.
Then ContentView is straightforward:
struct ContentView: View {
var user: User
var body: some View {
Text("signed-in username: \(user.userName)")
}
}