Variable is set but prints out nil - ios

Question

I am setting a variable in another viewcontroller and it is working inside didSet but in viewdidload it prints out nil
ViewController 1
let methodView = MethodViewController()
methodView.items = itemsSelected
presentDetail(newVC)
ViewController 2
class MethodViewController: UIViewController {
var items: [[String: Any]]? {
didSet {
print(items) // PRINTS OUT ITEMS NORMALLY
}
}
override func viewDidLoad() {
super.viewDidLoad()
print(items) // PRINTS OUT NIL
}
}

Answer 1

it is returning nil because you are setting the items by using one instance and when you present the screen and display your methodViewController. then you pass a new instance for same. instead set the items by using the same instance which you are using to present your controller
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
let methodView = StackProgramViewController() //instance 1 //your case methodView
methodView.items = itemsSelected //value is set and printed
}
#IBAction func present(_ sender: Any) {
let newVc = self.storyboard?.instantiateViewController(withIdentifier: "stack") as! StackProgramViewController //instance 2 while presenting //your case newVc
newVc.items = itemsSelected //set value here with second instance nstaead of creating methodView
present(newVc, animated: true, completion: nil)
}
hope it helps

Answer 2

Why not use an initializer method on your class, and then pass it explicitly to the present method like so:
MethodViewController
class MethodViewController: UIViewController {
var items: [[String: Any]]?
init(withItems items:[[String: Any]]?) {
self.items = items
super.init(nibName: "MethodViewController", bundle: nil)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func viewDidLoad() {
super.viewDidLoad()
print(items);
}
}
Previous View Controller
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
let items = [["Stack":"Overflow"]]
let methodView = MethodViewController(withItems: items)
self.present(methodView, animated: true, completion: nil)
}
}
I have tested it and it will print out the items passed, also note the require init() method which the compiler forces you to have. You will also need to specify the bundle and nibName depending on how you set up your views.
I should note this approach is if you aren't trying to load from the storyboard, but rather from a separate .xib file with the same name.