我在情节提要板上创建了CollectionView及其单元格，我尝试通过UICollectionViewFlowLayout在代码中设置单元格大小和边距，但是无论我做什么，边距都不会改变。更改情节提要的大小也不会改变任何内容 screenshot。 我总是得到这些利润： screenshot 我在做什么错了？
let itemsPerRow = 1
let sectionInsets = UIEdgeInsets(top: 1.0, left: 1.0, bottom: 1.0, right: 1.0)
extension VideoVC: UICollectionViewDelegateFlowLayout {
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let paddingSpace = sectionInsets.left + sectionInsets.right
let widthPerItem = collectionView.bounds.width - paddingSpace
return CGSize(width: widthPerItem, height: 265)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
return sectionInsets
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
return 5
}