How to retrieve and show user data from Firebase with swift? - swift

Question

I followed a tutorial to create a register and login screen with firebase and is already working, but now I want to create the screen "My account" with text fields where show the name, mail, etc.. of the user, so my question and I need help is how to get the data from firebase and show that information on that screen, how can I do it please?
I already read the firebase documentation https://firebase.google.com/docs/auth/ios/manage-users but I don't know how to proceed because Im learning programming/swift and I have to still improving my level
I attach the code of the sign up view
import UIKit
import FirebaseAuth
import FirebaseFirestore
import Firebase
class SignUpViewController: UIViewController {
#IBOutlet weak var nameField: UITextField!
#IBOutlet weak var lastNameField: UITextField!
#IBOutlet weak var emailField: UITextField!
#IBOutlet weak var passwordField: UITextField!
#IBOutlet weak var signUpButton: UIButton!
#IBOutlet weak var errorLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
setUpElements()
}
func setUpElements(){
//Hide the error label
errorLabel.alpha = 0
//Style the elements
Utilities.styleTextField(nameField)
Utilities.styleTextField(lastNameField)
Utilities.styleTextField(emailField)
Utilities.styleTextField(passwordField)
Utilities.styleFilledButton(signUpButton)
}
// Check the fields and validate that the data is correct. If everything is correct, this method returns nil. Otherwise, it returns the error message
func validateFields() -> String? {
// Check that all fields are filled in
if nameField.text?.trimmingCharacters(in: .whitespacesAndNewlines) == "" ||
lastNameField.text?.trimmingCharacters(in: .whitespacesAndNewlines) == "" ||
emailField.text?.trimmingCharacters(in: .whitespacesAndNewlines) == "" ||
passwordField.text?.trimmingCharacters(in: .whitespacesAndNewlines) == "" {
return "Please fill in all fields."
}
// Check if the password is secure
let cleanedPassword = passwordField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
if Utilities.isPasswordValid(cleanedPassword) == false {
// Password isn't secure enough
return "Please make sure your password is at least 8 characters, contains a special character and a number."
}
return nil
}
#IBAction func signUpTapped(_ sender: Any) {
// Validate the fields
let error = validateFields()
if error != nil {
// There's something wrong with the fields, show error message
showError(error!)
}
else {
// Create cleaned versions of the data
let firstName = nameField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
let lastName = lastNameField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
let email = emailField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
let password = passwordField.text!.trimmingCharacters(in: .whitespacesAndNewlines)
// Create the user
Auth.auth().createUser(withEmail: email, password: password) { (result, err) in
// Check for errors
if err != nil {
// There was an error creating the user
self.showError("Error creating user")
}
else {
// User was created successfully, now store the first name and last name
let db = Firestore.firestore()
db.collection("users").addDocument(data: ["firstname":firstName, "lastname":lastName, "uid": result!.user.uid ]) { (error) in
if error != nil {
// Show error message
self.showError("Error saving user data")
}
}
// Transition to the home screen
self.transitionToHome()
}
}
}
}
func showError(_ message:String) {
errorLabel.text = message
errorLabel.alpha = 1
}
func transitionToHome() {
let homeViewController = storyboard?.instantiateViewController(identifier: Constants.Storyboard.homeViewController) as? HomeViewController
view.window?.rootViewController = homeViewController
view.window?.makeKeyAndVisible()
}
}
And the actual code of my account view controller, just I add it the text fields, I don't know how to proceed
import UIKit
class MyAccountViewController: UIViewController {
#IBOutlet weak var nameField: UITextField!
#IBOutlet weak var lastnameField: UITextField!
#IBOutlet weak var emailField: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
}
I think that I provided all the info necessary, thank you