原本我是这样写的
// 滚动到指定位置
DispatchQueue.main.async { [weak self] in
let indexPath = IndexPath(row: self!.currentNumber - 1, section: 0)
self!.collectionView.scrollToItem(at: indexPath, at: .left, animated: true)
}
发现问题，UICollectionView在iOS14上滚动不到指定indexPath，而在iOS14以下是正常的，莫名其妙
解决方法，添加UICollectionView公开扩展方法，计算滚动偏移量
public extension UICollectionView {
func scrollTo(indexPath: IndexPath, animated: Bool = true) {
let attributes = collectionViewLayout.layoutAttributesForItem(at: indexPath)!
setContentOffset(attributes.frame.origin, animated: animated)
}
}
修改后的代码
// 初始滚动到指定位置
DispatchQueue.main.async { [weak self] in
let indexPath = IndexPath(row: self!.currentNumber - 1, section: 0)
self!.collectionView.scrollTo(indexPath: indexPath)
}
原文：https://www.cnblogs.com/lyjpost/p/13919590.html