Passing data in PageViewControllers swift - ios

Question

I have a page controller where I added UIViewControllers and display a bunch of form in each viewcontroller. The issue I am facing now is that I need to get the data supplied in each of the forms and save it which is done in the last view controller. I have tried using delegates but the moment the next button is clicked, the previous value stored becomes nil and only the value of the latest VC is displayed. How can I pass data in this textfields. Any help is appritated.
My delegate
protocol NextDelegate: AnyObject {
func next(pageIndex: Int, model: CreatePropertyModel)
func previous(pageIndex: Int, model: CreatePropertyModel)
}
how I created array of VC
lazy var controllers: [UIViewController] = {
let descVC = DescVC()
descVC.delegate = self
let priceVC = PriceVC()
priceVC.delegate = self
let featuresVC = FeaturesVC()
featuresVC.delegate = self
let picturesVC = PicturesVC()
picturesVC.delegate = self
return [descVC, priceVC, featuresVC, picturesVC]
}()
Model Example
class CreatePropertyModel: DictionaryEncodable {
var title: String?
var desc: String?
var property_type_id: Int?
var property_sub_type_id: Int?
var location_id: Int?
var currency: String?
var price: Int?
}

Answer 1

For all your steps, store it in a singleton.
protocol Answer {
var isDone: Bool { get }
}
class Answer1: Answer {
static public let updatedNotification = Notification.Name("Answer1Updated")
var name: String? {
didSet {
NotificationCenter.default.post(name: Answer1.updatedNotification, object: nil)
}
}
var isDone: Bool {
return name != nil
}
}
class Answer2: Answer {
var age: Int?
var isDone: Bool {
return age != nil
}
}
class Form {
static let shared = Form()
var answers: [Answer] = [Answer1(), Answer2()]
var isDone: Bool {
return answers.allSatisfy { $0.isDone == true }
}
private init() {}
func reset() {
answers = [Answer1(), Answer2()]
}
var answer1: Answer1? {
return Form.shared.answers.filter { $0 is Answer1 }.first as? Answer1
}
var answer2: Answer2? {
return Form.shared.answers.filter { $0 is Answer2 }.first as? Answer2
}
}
Then, in your view controller, read / write values like this.
class MyViewControllerForAnswer1: UIViewController {
var answer: Answer1? {
return Form.shared.answer1
}
var name: String? {
get {
return answer?.name
}
set {
answer?.name = newValue
}
}
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(answerUpdated(notification:)), name: Answer1.updatedNotification, object: nil)
}
#objc func answerUpdated(notification: Notification) {
// Update your content
}
}