UITableViewCell嵌套UICollectionView自适应高度

1.根据文字设定collectionViewCell的宽高：

override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
        let attributes = super.preferredLayoutAttributesFitting(layoutAttributes)
        var frame = titleLabel.text!.boundingRect(with: CGSize(width: .max, height: 30), options: .usesLineFragmentOrigin, attributes: [NSAttributedString.Key.font:titleLabel.font ?? UIFont.systemFont(ofSize: 15)], context: nil)
        frame.size.width += 10;
        frame.size.height = 30;
        attributes.frame = frame;
        
        return attributes;
    }

如果有其他控件，需要在frame里加上其他控件的宽高和间距

2.UITableViewCell 根据 UICollectionView 内容自适应高度：

override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
        
        let superSize = super.systemLayoutSizeFitting(targetSize, withHorizontalFittingPriority: horizontalFittingPriority, verticalFittingPriority: verticalFittingPriority)
        
        theaterCollectionView.layoutIfNeeded()
        
        let size = theaterCollectionView.collectionViewLayout.collectionViewContentSize
        
        return CGSize.init(width: superSize.width, height: size.height+superSize.height)
    }

首先要在tableViewCell里正确添加约束，一定要确保约束能够撑开 tableViewCell 否则将会得到错误的高度44。
然后重写 systemLayoutSizeFittingSize:withHorizontalFittingPriority:horizontalFittingPriority: 方法。