Why do my #State objects not retain their value? - ios

Question

I am trying to create a basic sign up screen. The screen appears fine however when I click submit, and an error is returned, the #State variables (such as $viewModel.firstName and $lastname reset back to empty strings, so my user loses all their progress.
Sign Up Screen
struct SignUpScreen: View {
#State
var firstName: String = ""
#State
var lastName: String = ""
#State
var birthday: String = ""
#State
var number: String = ""
#State
var email: String = ""
#State
var password: String = ""
#State
var confirmPassword: String = ""
#ObservedObject
var viewModel: SignUpViewModel = SignUpViewModel()
var body: some View {
ZStack {
VStack {
VClearBackground()
Spacer()
}
ScrollView {
VStack(alignment: .leading) {
Group {
PreHeaderText(header: "Get Started")
.alignmentGuide(.leading, computeValue: {d in
d[.leading]
})
.padding(EdgeInsets.init(top: 32, leading: 0, bottom: 0, trailing: 0))
HeaderText(header: "Create Account")
EditText(hint: "John", text: $viewModel.firstName, label: "FIRST NAME", textContentType: UITextContentType.name)
EditText(hint: "Doe", text: $lastName, label: "LAST NAME", textContentType: UITextContentType.name)
EditText(hint: "01/01/2001", text: $birthday, label: "BIRTHDAY")
EditText(hint: "[phone])", text: $number, label: "MOBILE NUMBER", textContentType: UITextContentType.telephoneNumber, keyboardType: UIKeyboardType.phonePad)
EditText(hint: "email#exmaple.com", text: $email, label: "EMAIL", textContentType: UITextContentType.emailAddress)
EditText(hint: "********", text: $password, label: "PASSWORD", textContentType: UITextContentType.newPassword)
EditText(hint: "********", text: $confirmPassword, label: "CONFIRM PASSWORD", textContentType: UITextContentType.newPassword)
}
Group {
if self.viewModel.error != nil {
HStack {
Spacer()
Text(viewModel.error ?? "")
.foregroundColor(ColorTheme.error.color)
Spacer()
}
.padding()
}
HStack {
Spacer()
VowerButton(text: "Submit") {
self.viewModel.signUp(firstName: self.viewModel.firstName, lastName: self.lastName, email: self.email, birthday: self.birthday, phoneNumber: self.number, password: self.password, confirmPassword: self.confirmPassword)
}
Spacer()
}
.padding()
HStack {
Spacer()
NavigationLink(destination: LoginScreen(), isActive: $viewModel.goToLogin) {
CtaText(text: "Have an account?", cta: "Login") {
self.viewModel.onGoToLoginClicked()
}
}
.padding()
Spacer()
}
Spacer()
}
}
}
.padding(EdgeInsets.init(top: 16, leading: 16, bottom: 16, trailing: 16))
.frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .leading)
}
.background(LinearGradient(gradient: Gradient(colors: [.black, ColorTheme.brandPurple.color]), startPoint: .top, endPoint: .bottom))
.edgesIgnoringSafeArea(.all)
}
}
Sign Up ViewModel
class SignUpViewModel : ObservableObject {
#State
var firstName: String = ""
#Published
var error: String? = nil
#Published
var goHome: Bool = false
#Published
var goToLogin: Bool = false
func onGoToLoginClicked() {
self.goToLogin = true
}
func signUp(firstName: String, lastName: String, email: String, birthday: String, phoneNumber: String, password: String, confirmPassword: String) {
if (firstName.count < 3) {
error = "Please enter first name"
return
}
if (lastName.count < 3) {
error = "Please enter last name"
return
}
if (!email.isEmail()) {
error = "Pleaes enter valid email"
return
}
if (birthday.isEmpty) {
error = "Pleae enter valid birthday"
return
}
if (!phoneNumber.isDigits) {
error = "Please enter valid phone number"
return
}
if (password.count < 8) {
error = "Please enter a password that is at least 8 characters long"
}
if (password != confirmPassword) {
error = "Password do not match"
}
Auth.auth().createUser(withEmail: email, password: password, completion: { authResult, error in
if authResult != nil {
self.goHome = true
} else {
self.error = error?.localizedDescription
}
})
}
}
EditText View
struct EditText: View {
var hint: String
#Binding
var text: String
var label: String = ""
var defaultValue = ""
var textContentType: UITextContentType? = .none
var keyboardType: UIKeyboardType = .default
private func initializeDefaultValue() {
DispatchQueue.main.async {
self.text = self.defaultValue
}
}
var body: some View {
initializeDefaultValue()
return VStack(alignment: .leading) {
Text(label).font(.system(size: 12)).bold()
.foregroundColor(ColorTheme.text.color)
HStack {
TextField(hint, text: $text)
.lineLimit(1)
.textContentType(textContentType)
.keyboardType(keyboardType)
.foregroundColor(ColorTheme.text.color)
}
Divider().background(Color(ColorTheme.brandBlue.value))
}
.padding(EdgeInsets.init(top: 12, leading: 0, bottom: 8, trailing: 0))
}
}

Answer 1

Ok, now I see (continuing from your second question, which I answered first). #State should be used in View it is designed for it. In ObservableObject you have to use #Published, so below is how it should be
class SignUpViewModel : ObservableObject {
#Published
var firstName: String = ""