如何快速在委托sizeForItemAtIndexPath中创建collectionview单元格的对象

Question

像在Objective中一样，我们可以如下获取CollectionViewCell的对象。 Swift有一些问题：

-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
DatasetCell *datasetCell = (DatasetCell *)[collectionView cellForItemAtIndexPath:indexPath];
(DatasetCell *)[collectionView cellForItemAtIndexPath:indexPath];
datasetCell.backgroundColor = [UIColor skyBlueColor]; 
}

我的快速代码是：

  func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

    let datasetCell: DatasetCell = collectionView.cellForItemAtIndexPath(indexPath) as! DatasetCell

    datasetCell.backgroundColor = UIColor.blueColor()
}

Answer 1

将该方法转换为快速方法，如下所示

 func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

    let datasetCell =  collectionView(collectionView, cellForItemAtIndexPath: indexPath) as DatasetCell
    datasetCell.backgroundColor = UIColor.blueColor()

}