Can't get the value of a var in another class - ios

Question

I'm trying to get the value of a String var from an another class, but when i'm using it on the new class, the value is empty.
I've got the MainViewController.swift class with :
var movieIDSelected = String()
#IBAction func tapPosterButton(_ sender: UIButton) {
switch sender.tag
{
case 101: movieIDSelected = theaterMovieID[0]
print(movieIDSelected) //The value isn't empty
break
}
}
And the second MovieViewController.swift class with :
var HomeView = ViewPop()
override func viewDidLoad() {
super.viewDidLoad()
let movieID = HomeView.movieIDSelected
print(movieID) //The value is empty
}

Answer 1

With your current code try this in MainVC
if let home = UIApplication.shared.keyWindow?.rootViewController as? ViewPop {
print("home exists ",home.movieIDSelected)
}
//
but you should have only 1 segue to the destinationVC and link it to the VC not a segue for every button , then implement prepareForSegue and fire performSegue inside the button action to make the segue
//
#IBAction func tapPosterButton(_ sender: UIButton) {
switch sender.tag
{
case 101: movieIDSelected = theaterMovieID[0]
print(movieIDSelected) //The value isn't empty
self.performSegue(withIdentifier: "goToNext", sender:1)
break
}
}
//
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let des = segue.destination as! MovieViewController
des.sendedValue = self.movieIDSelected
des.buttonNumber = sender as! Int
}
//
class MovieViewController : UIViewController {
var sendedValue = ""
var buttonNumber = 0 // default value won't affect
}