Struggling to pass data to UI - Swift - swift

Question

Good day, I'm trying to pass data to my Profile UI View.
This is my Customer Class:
class Customer {
// Creating a customer
let name: String
let surname: String
let contactNo: String
let email: String
init(name: String,surname: String,contactNo: String,email: String) {
self.name = name
self.surname = surname
self.contactNo = contactNo
self.email = email
}
}
This is my code whereby I try to parse data from Firestore to display a customers details:
class ProfileCus: UIViewController {
// Labels to display data
#IBOutlet weak var nameLabel: UILabel!
#IBOutlet weak var surnameLabel: UILabel!
#IBOutlet weak var emailLabel: UILabel!
#IBOutlet weak var contactLabel: UILabel!
// Reference to customer collection in Firestore
private var customerRefCollection: CollectionReference!
// Customer Object
private var customer: Customer?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
customerRefCollection = Firestore.firestore().collection("customers")
nameLabel.text = customer?.name
surnameLabel.text = customer?.surname
emailLabel.text = customer?.email
contactLabel.text = customer?.contactNo
}
// This function notifies the view controller that the view is about to load so it is best to acquire the data in here before the view loads so that it will be ready to display.
override func viewWillAppear(_ animated: Bool) {
// Get the current user ID
let userID = Auth.auth().currentUser?.uid
// Locate the user information on Firestore
customerRefCollection.document(userID!).getDocument { (snapshot, error) in
if let err = error {
debugPrint("Error fetching documents: \(err)")
}
else {
// Ensure that if there's nothing in the document that the function returns
guard let snap = snapshot else {return}
// Parse the data to the customer model
let data = snap.data()
let name = data?["name"] as? String ?? ""
let surname = data?["surname"] as? String ?? ""
let email = data?["email"] as? String ?? ""
let contact = data?["contact no"] as? String ?? ""
// Create the customer and pass it to the global variable
let cus = Customer(name: name, surname: surname, contactNo: contact, email: email)
self.customer = cus
}
}
}
}
Everything on the Firestore side is working fine and I am able to read/retrieve data but I'm struggling to pass the data to my UI via my Customer Class. Using print statements it seems as if the customer object is nil.
Output once the code runs

Answer 1

func getDataFromFirebase(completion:#escaping() -> ()){
let userID = Auth.auth().currentUser?.uid
// Locate the user information on Firestore
customerRefCollection.document(userID!).getDocument { (snapshot, error) in
if let err = error {
debugPrint("Error fetching documents: \(err)")
}
else {
// Ensure that if there's nothing in the document that the function returns
guard let snap = snapshot else {return}
// Parse the data to the customer model
let data = snap.data()
let name = data?["name"] as? String ?? ""
let surname = data?["surname"] as? String ?? ""
let email = data?["email"] as? String ?? ""
let contact = data?["contact no"] as? String ?? ""
// Create the customer and pass it to the global variable
let cus = Customer(name: name, surname: surname, contactNo: contact, email: email)
self.customer = cus
}
completion()
}
}
getDataFromFirebase{
customerRefCollection = Firestore.firestore().collection("customers")
nameLabel.text = customer?.name
surnameLabel.text = customer?.surname
emailLabel.text = customer?.email
contactLabel.text = customer?.contactNo
}
So what you're basically doing here is you're first getting the data from the firebase and only after this work is done, hence the completion block you will be setting your data to the view. You can call the method simply in viewDidLoad.