Change background of specific UICollectionView cells swift - ios

Question

I am trying to change the background of the first two cells in my collection view i have tried this code
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let width = self.view.frame.width
let height = self.view.frame.height
return CGSize(width: width / 2.2 , height: height / 6)
}
override func didRotate(from fromInterfaceOrientation: UIInterfaceOrientation) {
MyCollectionView.reloadData()
}
#IBAction func Back(_ sender: Any) {
performSegue(withIdentifier: "fourtothree", sender: nil)
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return ScoreArray.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let Cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell
let MyCell = Cell.viewWithTag(1) as! UILabel
MyCell.text = ScoreArray[indexPath.row]
if indexPath.row == 0 {
Cell.backgroundColor = UIColor.gray
MyCell.font = UIFont.boldSystemFont(ofSize: 16.0)
}
if indexPath.row == 1 {
Cell.backgroundColor = UIColor.gray
MyCell.font = UIFont.boldSystemFont(ofSize: 16.0)
}
return Cell
}
It changes the color of the first two cells which is great. however when I rotate to landscape or scroll it changes the background of different cells not just the first two.
Question: How can I change the background of only the first two cells no mater what the user does?

Answer 1

Since your cell get reused, you need to provide the default color for other cell.
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let Cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell
let MyCell = Cell.viewWithTag(1) as! UILabel
MyCell.text = ScoreArray[indexPath.row]
if indexPath.row == 0 || indexPath.row == 1 {
Cell.backgroundColor = UIColor.gray
MyCell.font = UIFont.boldSystemFont(ofSize: 16.0)
} else {
Cell.backgroundColor = UIColor.white //change with your default color
}
return Cell
}

Answer 2

you can change the color of ay cell but as in cellForItemAt indexPath function you are using
let Cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell that statement reuse the cell to reduce the memory usage , So to overcome this problem use
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let Cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CollectionViewCell
let MyCell = Cell.viewWithTag(1) as! UILabel
MyCell.text = ScoreArray[indexPath.row]
MyCell.font = UIFont.boldSystemFont(ofSize: 16.0)
if indexPath.row == 0 || indexPath.row == 1 {
Cell.backgroundColor = UIColor.gray
}
else {
Cell.backgroundColor = UIColor.clear
}
return Cell
}