cell variable is nil where value was set collectionview index path

Question

i spend lot of time .. but i can't figure out why it is not working .. cell for index path called and set value properly but cell class i found nil value .. if your need any information then let me know .

in my collectionview index path

in collectionview cell

here is my code :

for collectionview :

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: menuBarItemDetailId, for: indexPath) as! MenuBarItemDetail
        cell.shopCategory = "600"
        print(cell.shopCategory)
        return cell
    }

for cell :

class MenuBarItemDetail: UICollectionViewCell , UITableViewDataSource , UITableViewDelegate {
    var shopCategory : String?

    override init(frame: CGRect) {
        super.init(frame: frame)

         print("shopCategory :-> ...i am calling from cell :\(shopCategory)")
}

yes ! I already done that one please check 1st image but no result .. do you meant that one — cristan lika, Jan 17 '17 at 10:40
@cristanlika no need of these in cell class UITableViewDataSource , UITableViewDelegate at first because this is collection view cell so all delegates you need to put in your view controller and remove init function. no need. you can use awakeFromNib — Sagar Snehi, Jan 17 '17 at 10:57

dahiya_boy · Accepted Answer · 2020-01-14T05:27:22.570

5

Because your awakeFromNib method called first and then cellForRow .You are assigning the value of variable in cellForRow so when first project executes its value is nil.

Solution

your variable in your custom cellclass
```
var myVar : String?
```

Create a method in your custom cellclass

func myMethod(str : String){
    myVar = str
    print("var : \(myVar)")        
}

in cellForItem, call your function like this
```
cell.myMethod(str: "343")
```

Output

edited Jan 14 '20 at 05:27

answered Jan 17 '17 at 10:46

dahiya_boy

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first of all i did not use awakeFromNib anywhere in my project second if so what is that solution . could you guide me what can do ? – cristan lika Jan 17 '17 at 10:51
1

Init method also called first, check it out. – dahiya_boy Jan 17 '17 at 10:52
yes seem . what can i do ? what is the solution please – cristan lika Jan 17 '17 at 10:55
@cristanlika Check the solution with output I got. Accept the answer and upvote if it works for you otherwise write your problem. – dahiya_boy Jan 17 '17 at 11:12

score 3 · Answer 2 · answered Jan 17 '17 at 10:57

When you are writing

let cell = collectionView.dequeueReusableCell(withReuseId`entifier: "MenuBarItemDetail", for: indexPath) as! MenuBarItemDetail`

At that time "override init(frame: CGRect)" is called. and no value is assigned to shopCategory at the time of init that's the reason you are getting nil.

Add a function "getShopCategory" into MenuBarItemDetail and when every you want to access the value of shopCategory you can get that using getShopCategory function.

import Foundation
import UIKit

    class MenuBarItemDetail: UICollectionViewCell  {
        var shopCategory : String?

        func  getShopCategory()  {
         print("shopCategory :-> ...i am calling from cell :\(shopCategory)")
        }


    }

Controller Class

 func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MenuBarItemDetail", for: indexPath) as! MenuBarItemDetail
        cell.shopCategory = "600"
        print(cell.shopCategory)
        cell.getShopCategory()
        return cell
    }

cell is the current instance of MenuBarItemDetail so it will return assigned value of shopCategory

Please let me know if it's working for you. Thank you

cell variable is nil where value was set collectionview index path

2 Answers2