UICollectionviewCell backgroundColor not Change when selected

Question

I'm trying to change backgorund color of cell when its selected. But cell background color not changing.

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CategoryCollectionViewCell
    let category = self.categories[indexPath.row]
    switch cell.isSelected {
    case true:
        cell.backgroundColor = .black
    default:
        cell.backgroundColor = .white
    }
    cell.setNeedsDisplay()    
}

Answer 1

You don't need to manually change the background color upon selection. UICollectionViewCell has a property called selectedBackgroundView precisely for this purpose.

Use it in your collectionView(_:cellForItemAt:) delegate method as follows:

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! CategoryCollectionViewCell

    cell.selectedBackgroundView = UIView(frame: cell.bounds)
    cell.selectedBackgroundView!.backgroundColor = .black

    return cell
}

Answer 2

Try the following in you didSelect delegate method:

override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    let selectedCell = collectionView.cellForItemAtIndexPath(indexPath)

    selectedCell?.backgroundColor = UIColor.blueColor()
}