首先请看以下代码，运行结果如何。

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import UIKit

class ViewController: UIViewController {
    private lazy var tableView: UITableView = {
        let tableView = UITableView(frame: .zero, style: .plain)
        tableView.delegate = self
        tableView.dataSource = self
        tableView.tableHeaderView = tableHeaderView
        tableView.translatesAutoresizingMaskIntoConstraints = false
        tableView.register(UITableViewCell.self, forCellReuseIdentifier: "CELL")
        return tableView
    }()
    private lazy var tableHeaderView: UIView = {
        let avatarImageView: UIImageView = {
            let imageView = UIImageView(image: UIImage(systemName: "person.circle"))
            imageView.translatesAutoresizingMaskIntoConstraints = false
            return imageView
        }()
        let nameLabel: UILabel = {
            let label = UILabel()
            label.numberOfLines = 0
            label.text = "洛阳城里见秋风，欲作家书意万重"
            label.translatesAutoresizingMaskIntoConstraints = false
            return label
        }()
        
        let view = UIView(frame: CGRect(origin: .zero,
                                        size: CGSize(width: UIScreen.main.bounds.width, height: 150)))
        view.addSubview(avatarImageView)
        view.addSubview(nameLabel)
        NSLayoutConstraint.activate([
            avatarImageView.widthAnchor.constraint(equalToConstant: 50),
            avatarImageView.heightAnchor.constraint(equalToConstant: 50),
            avatarImageView.centerYAnchor.constraint(equalTo: view.centerYAnchor),
            avatarImageView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 16),
            
            nameLabel.centerYAnchor.constraint(equalTo: view.centerYAnchor),
            nameLabel.leadingAnchor.constraint(equalTo: avatarImageView.trailingAnchor, constant: 12),
            nameLabel.trailingAnchor.constraint(lessThanOrEqualTo: view.trailingAnchor, constant: -16),
        ])
        return view
    }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        view.addSubview(tableView)
        NSLayoutConstraint.activate([
            tableView.topAnchor.constraint(equalTo: view.topAnchor),
            tableView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
            tableView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            tableView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
        ])
    }
}

extension ViewController: UITableViewDelegate, UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 20
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "CELL", for: indexPath)
        cell.textLabel?.text = "\(indexPath.row)"
        return cell
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        print(indexPath)
    }
}

以上，运行之后页面显示正常，但控制台输出了一些约束错误信息：

Unable-to-simultaneously-satisfy-constraints

先说解决方法，nameLabel 的约束稍加修改：

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...
        nameLabel.centerYAnchor.constraint(equalTo: view.centerYAnchor),
        nameLabel.leadingAnchor.constraint(equalTo: avatarImageView.trailingAnchor, constant: 12),
    ])
    let nameLabelTrailingConstraint =
        nameLabel.trailingAnchor.constraint(lessThanOrEqualTo: view.trailingAnchor, constant: -16)
    nameLabelTrailingConstraint.priority = .defaultHigh
    nameLabelTrailingConstraint.isActive = true
    return view
}()

override func viewDidLoad() {
...

当自定义 tableView 的 tableHeaderView 或 tableFooterView 时会遇到这样的错误，如果设置
tableHeaderView.translatesAutoresizingMaskIntoConstraints = false
页面显示就更不对了，解决方法就是设置下约束的优先级，就如上边设置 nameLabel 的 trailingConstraint 的优先级。