注意： – 由于AutoLayout,无法更改sizeForItemAtIndexPath.

以下是我用过的代码：

func collectionView(collectionView: UICollectionView,layout collectionViewLayout: UICollectionViewLayout,sizeForItemAtIndexPath indexPath:NSIndexPath ) -> CGSize {

          return CGSize(width: (self.objKeypadCollectionView.frame.size.width/3)-10,height: (self.objKeypadCollectionView.frame.size.height/4)-10)
    }

func collectionView(collectionView: UICollectionView,cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {

        let objKeypadCollectionViewCell = collectionView.dequeueReusableCellWithReuseIdentifier("idKeypadCollectionViewCell",forIndexPath: indexPath) as! KeypadCollectionViewCell

        if (self.numberArray[indexPath.item])=="asda" {
            objKeypadCollectionViewCell.lblNumber.text = ""
            objKeypadCollectionViewCell.imgPrint.hidden = false
        }
        else if (self.numberArray[indexPath.item])=="Derterel" {
            objKeypadCollectionViewCell.lblNumber.text = self.numberArray[indexPath.item]
            objKeypadCollectionViewCell.imgPrint.hidden = true
        }
        else {
            objKeypadCollectionViewCell.imgPrint.hidden = true
            objKeypadCollectionViewCell.lblNumber.text = self.numberArray[indexPath.item]
            objKeypadCollectionViewCell.layer.borderColor = UIColor.lightGrayColor().CGColor
            objKeypadCollectionViewCell.layer.borderWidth = 1
            objKeypadCollectionViewCell.layer.cornerRadius = objKeypadCollectionViewCell.frame.size.width/2
        }
        return objKeypadCollectionViewCell
    }