multiple cells selected on scrolling [reuse cells problem]

Question

I have a collectionViewCell which contains an image and a label. When I select a cell and scroll ahead I find other cell being selected. Also when I scroll back I find the o

Answer 1

Maintain global variable in your controller

var mLastSelectedIndex = -1

Whenever cellForRowAtIndexPath method called check if current cell is selected or not .If this is selected One update its UI. I suggest you to change selected cell UI on cell class only. This way you can easily manage cell tapping and helps you writing clean code.

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
  let cell = attachProfilesCollectionView.dequeueReusableCell(withReuseIdentifier: "attachCells", for: indexPath) as? attachUsersCell
  cell!.subscribedUserId = self.followedUsers[indexPath.row].userId
  cell?.profileNameToAttah.text = self.followedUsers[indexPath.row].fullName
  cell?.profileImageToAttch.loadImagesWithUrl(from:   self.followedUsers[indexPath.row].ImagePath)
// here update selected index path
  if mLastSelectedIndex == indexPath.row {
      cell?.isSelected = true
  }
else{ 
    cell?.isSelected = false
  }

   return cell!
}

Update last selected index on cell tapped.

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

    guard mLastSelectedIndex != IndexPath.row else{return}
    let indexpath = IndexPath(row:mLastSelectedIndex, section: 0)
    mColllectionView.cellForItem(at: indexpath)?.isSelected = !mColllectionView.cellForItem(at: indexpath)!.isSelected
    mLastSelectedIndex = IndexPath.row 
  }

In your attachUsersCell.swift declare isSelected property of cell . The default value of this property is false, which indicates that the cell is not selected.

override var isSelected: Bool{
    didSet{
        if isSelected {

          setSelectedUI()

        }
        else{

            setUnSelectedUI()

        }

    }
}

func setSelectedUI(){
     borderColor = UIColor.systemOrange
     borderWidth = 2
     cornerRadius = 8
      clipsToBounds = true
}

func setUnSelectedUI(){
    // reset to default ui
}

Hope this helps!