Issue in Passing data from UicollectionView controller - ios

Question

I have seen couple of posts but not able to figure out the issue
I want to pass data from UICollectionView Controller to my UIViewController , Here are the details
func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "Selection2" {
if let indexPath = self.collectionView?.indexPath(for: sender as! UICollectionViewCell) {
let detailVC = segue.destination as! SelectionViewController
//
let item = items1[indexPath.row]
//passing the item name which is selected
detailVC.label1.text = item.name1
}
}
}
And here is the SelectionViewController code :
import UIKit
class SelctionViewController: UIViewController {
var label1 : UILabel!
#IBOutlet weak var Label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
Label.text = self.label1.text
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
But when i run this i am not able to pass values and getting the following error :
fatal error: unexpectedly found nil while unwrapping an Optional value
Please suggest how this can be corrected , Thanks

Answer 1

I will suggest you the following approach. write below code in didSelectItemAt method.
let detailVC = self.storyboard?.instantiateViewController(withIdentifier: "Selection2") as! SelectionViewController
let item = items1[indexPath.row]
//Create string property itemName and pass the value
detailVC.itemName = item.name1
self.navigationController?.pushViewController(detailVC, animated: true)
Assing itemName to laber in SelectionViewController like below.
self.Label.text = itemName

Answer 2

#lazyCoder , thanks for helping me out
override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let detailVC = self.storyboard?.instantiateViewController(withIdentifier: "Selection2") as! SelctionViewController
detailVC.itemName = self.items1[indexPath.row].name1
self.navigationController?.pushViewController(detailVC, animated: true)
}
This code is working perfectly fine now ..Cheers

Answer 3

Instead of using UIlabel label1, declare string variable eg. title. and Change the following lines in your code.
class SelctionViewController: UIViewController {
var title = ""
#IBOutlet weak var Label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
Label.text = title
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
prepareForSegue method: instead of detailVC.label1.text, use detailVC.title
func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "Selection2" {
if let indexPath = self.collectionView?.indexPath(for: sender as! UICollectionViewCell) {
let detailVC = segue.destination as! SelectionViewController
let item = items1[indexPath.row]
detailVC.title = item.name1 // instead of detailVC.label1.text, use detailVC.title
}
}
}