how to prepare segue can't selected pass label text to text string

Question

I have prepared a segue but when the user selects a cell it is not pass label text to text in detail View

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "viewNumberSegue" {
        guard let indexPath = sender as? IndexPath else { return }

        let collectionCell = collectionView.cellForItem(at: indexPath) as! ItemCollectionViewCell
        let textToPass = collectionCell.ItemLabel.text

        let detailVC = segue.destination as? DetailViewController
        detailVC?.number = textToPass!
    }
}


// MARK: UICollectionViewDelegate
extension GridCollectionViewController {
    

    override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

          self.performSegue(withIdentifier: "viewNumberSegue", sender: indexPath)

  }
}

DetailVC

import UIKit

class DetailViewController: UIViewController {
    
    var number:String = "" 
    @IBOutlet weak var numberLabel: UILabel!
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        print(number)
        numberLabel.text = number
    }
}

Answer 1

Instead of passing the indexPath in sender, it's better to directly pass the number as sender.

extension GridCollectionViewController {

   override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
     let collectionCell = collectionView.cellForItem(at: indexPath) as! ItemCollectionViewCell
     let textToPass = collectionCell.ItemLabel.text

     self.performSegue(withIdentifier: "viewNumberSegue", sender: textToPass)
  }
}


override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
   if segue.identifier == "viewNumberSegue" {
     guard let number = sender as? String else { return }

     let detailVC = segue.destination as? DetailViewController
     detailVC?.number = number
  }
}