在UITableView标头内居中UIImageView

// 自定义标头视图类
class CustomHeaderView: UITableViewHeaderFooterView {
    var headerImageView: UIImageView!
    
    override init(reuseIdentifier: String?) {
        super.init(reuseIdentifier: reuseIdentifier)
        
        // 创建UIImageView并设置约束
        headerImageView = UIImageView()
        headerImageView.translatesAutoresizingMaskIntoConstraints = false
        addSubview(headerImageView)
        
        NSLayoutConstraint.activate([
            headerImageView.centerXAnchor.constraint(equalTo: centerXAnchor),
            headerImageView.centerYAnchor.constraint(equalTo: centerYAnchor)
        ])
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

// 在UITableView的代理方法中使用自定义的标头视图类
func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    let headerView = tableView.dequeueReusableHeaderFooterView(withIdentifier: "CustomHeaderView") as? CustomHeaderView
    
    // 设置UIImageView的图片
    headerView?.headerImageView.image = UIImage(named: "header_image")
    
    return headerView
}

func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
    return 100.0 // 设置标头视图的高度
}