如何在viewforheadersection中添加磁贴？

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    let headerView = UIView(frame: CGRect(x: 0, y: 0, width: tableView.frame.width, height: 50))
    headerView.backgroundColor = UIColor.lightGray
    
    let tileView = UIView(frame: CGRect(x: 10, y: 10, width: headerView.frame.width - 20, height: headerView.frame.height - 20))
    tileView.backgroundColor = UIColor.white
    tileView.layer.cornerRadius = 5.0
    tileView.layer.shadowColor = UIColor.gray.cgColor
    tileView.layer.shadowOffset = CGSize(width: 0, height: 2)
    tileView.layer.shadowOpacity = 0.5
    
    let titleLabel = UILabel(frame: CGRect(x: 10, y: 10, width: tileView.frame.width - 20, height: 30))
    titleLabel.text = "磁贴标题"
    titleLabel.textAlignment = .center
    
    tileView.addSubview(titleLabel)
    headerView.addSubview(tileView)
    
    return headerView
}