Swift:如何更改imageView颜色，使其看起来像是被敲击过的

Question

我在一个单元格中有一个imageView。然而，当我点击那个单元格时，没有任何视觉指示它被点击了。我希望它看起来像按钮内的imageView，当你点击按钮时，它会改变颜色。

  func collectionView(collectionView: UICollectionView, shouldHighlightItemAtIndexPath indexPath: NSIndexPath) -> Bool {
    let cell: UICollectionViewCell = collectionView.cellForItemAtIndexPath(indexPath)
    // what do i do with the cell.imageView to change it's state to look like it was tapped?
  }

Answer 1

  func collectionView(collectionView: UICollectionView, shouldHighlightItemAtIndexPath indexPath: NSIndexPath) -> Bool {
    let cell: IconCell = collectionView.cellForItemAtIndexPath(indexPath) as! IconCell
    cell.imageView.alpha = 0.5
    return true
  }
  func collectionView(collectionView: UICollectionView, didUnhighlightItemAtIndexPath indexPath: NSIndexPath) {
    let cell: IconCell = collectionView.cellForItemAtIndexPath(indexPath) as! IconCell
    cell.imageView.alpha = 1.0
  }