How to retrieve filled TextField from persistence - ios

Question

I have an error when loading secondViewController with a textField and an action button so the user can fill it with some number and get it saved to UserDefaults
The idea is to be able to come back to secondVC and that the TextField shows there with the same value that input originally by the User
class MainViewController: UIViewController {
#IBOutlet weak var A3TextField: UITextField!
#IBAction func calc(_ sender: Any) {
let A3 = Cell(name: "A3", sheet: "", value: Double(A3TextField.text!)!)
print(A3)
Cell.saveCellsUserDefaults(cells: [A3], forKey: "main")
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
}
class SecondViewController: UIViewController {
#IBOutlet weak var B3TextField: UITextField!
#IBAction func calc2(_ sender: Any) {
let B3 = Cell(name: "B3", sheet: "", value: Double(B3TextField.text!)!)
print(B3)
// persist
Cell.saveCellsUserDefaults(cells: [B3], forKey: "second")
}
override func viewDidLoad() {
super.viewDidLoad()
// retrieve from persists and draw in TextField
let cellB3FromUD = Cell.getCellsUserDefaults(forKey: "second")
print("---> cellB3FromUD \(cellB3FromUD[0].value)")
B3TextField.text = "\(cellB3FromUD[0].value)"
}
}
struct Cell: Codable {
var name: String = ""
var sheet: String = ""
var value: Double = 0
init(name: String, sheet: String, value: Double) {
self.name = name
self.sheet = sheet
self.value = value
}
static func saveCellsUserDefaults(cells: [Cell], forKey: String) {
let encoder = JSONEncoder()
if let encoded = try? encoder.encode(cells) {
let defaults = UserDefaults.standard
defaults.set(encoded, forKey: forKey)
}
}
static func getCellsUserDefaults(forKey: String)-> [Cell] {
var cells = [Cell]()
let decoder = JSONDecoder()
if let cellData = UserDefaults.standard.data(forKey: forKey) {
if let cellX = try? decoder.decode([Cell].self, from: cellData) {
cells = cellX
return cellX
}
}
return cells
}
}