Swift: How should I transfer data to other class in this case?-CodePudding

I was designed to present the pop-up screen when the removeReview button is pressed.

The removeReview button is placed in ReviewItem.swift.

Right below is parts of the codes that is from ReviewItem.swift that I wrote. (The class type is the UITableViewCell)

weak var viewController: UIViewController?
var passwords: String = ""
var reviewNum: String = ""

@IBAction func removeReview(_ sender: Any) {
        
  print("ReviewItem - removeReview function called")
     
  print("Passwords: \(passwords)")
  print("Review_number: \(reviewNum)")
        
  let PopUpVC = PopUpVC()
  PopUpVC.pw = self.passwords
  PopUpVC.reviewDoc = self.reviewNum
        
  print(PopUpVC.pw)
  print(PopUpVC.reviewDoc)
        
  let storyboard = UIStoryboard.init(name: "PopUp", bundle: nil)
  let alertPopUpVC = storyboard.instantiateViewController(withIdentifier: "VerifyPasswords")
  alertPopUpVC.modalPresentationStyle = .overCurrentContext
  alertPopUpVC.modalTransitionStyle = .crossDissolve

  viewController?.present(alertPopUpVC, animated: true, completion: nil)
        
}

Though in the beginning of the code, I initialized the passwords and reviewNum as "", in the other swift file, I wrote the code

let cell = tableView.dequeueReusableCell(withIdentifier: String(describing: ReviewItem.self), for: indexPath) as! ReviewItem
cell.viewController = self
cell.passwords = reviews[indexPath.section].password
cell.reviewNum = reviews[indexPath.section].reviewNum

so the passwords and reviewNum is changed and print("Password: \(passwords)") and print("Review_number: \(reviewNum)") is successfully work.

So I wrote the code similarly. However, in this case (The first codes that I uploaded),

 let PopUpVC = PopUpVC()
 PopUpVC.pw = self.passwords
 PopUpVC.reviewDoc = self.reviewNum

the value is not changed.

Right below is the parts of the PopUpVC

class PopUpVC: UIViewController{

    var reviewDoc: String = ""
    var pw: String = ""
    
    override func viewDidLoad() {
        super.viewDidLoad()
        print("PopUpVC - UIViewController called")
        print(pw)
        print(reviewDoc)
    }

 ...

}

I hope someone can tell me what is the problem and how to solve the problem.

Thank you.

CodePudding user response：

You're not initialising your PopUpVC properly. Here's how you should do it:

@IBAction func removeReview(_ sender: Any) {
        
  print("ReviewItem - removeReview function called")
     
  print("Passwords: \(passwords)")
  print("Review_number: \(reviewNum)")
        
  let storyboard = UIStoryboard(name: "PopUp", bundle: nil)
  let alertPopUpVC = storyboard.instantiateViewController(withIdentifier: "VerifyPasswords") as! PopUpVC // make sure this identifier is a PopUpVC class!!!

  alertPopUpVC.pw = self.passwords
  alertPopUpVC.reviewDoc = self.reviewNum

  alertPopUpVC.modalPresentationStyle = .overCurrentContext
  alertPopUpVC.modalTransitionStyle = .crossDissolve

  viewController?.present(alertPopUpVC, animated: true, completion: nil)
        
}

You were initialising your PopUpVC and presenting a different instance initialised via Storyboard.

I hope this helps! :)