Semi self-sizing CollectionViewCell with autolayout

swift

var COLLECTIONVIEWHEIGHT: CGFloat!
var LINESPACING: CGFloat!
var cachedHeights = [String:CGFloat]()


class WordTileCollectionViewCell: UICollectionViewCell {
  
  @IBOutlet weak var wordLabel: UILabel!
    
    
    var identifier: String!
  
  var word: String = "" {
    didSet {
      wordLabel.text = word
    }
  }
  
  override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
    let toReturn = super.preferredLayoutAttributesFitting(layoutAttributes)
    
    if identifier == "WordCell3" {
        
        let totalHeight = cachedHeights.values.reduce(0, +)
        let finalHeight = COLLECTIONVIEWHEIGHT - totalHeight
        
        let newFrame = toReturn
        
        
        newFrame.frame = CGRect(x: toReturn.frame.minX, y: toReturn.frame.minY, width: toReturn.frame.width, height: finalHeight)
        newFrame.bounds = CGRect(x: 0, y: 0, width: toReturn.frame.width, height: finalHeight)
        
        return newFrame
    } else {
        cachedHeights[identifier] = toReturn.bounds.height + LINESPACING
    }
    
    return toReturn
  }
}