ios - UITableView 单元格嵌入 View Controller 自动调整大小？

Question

我正在尝试使用嵌入式 View Controller 来保持代码整洁，并且只执行一小部分功能。因此，我已经采取了在 TableView 单元格中嵌入 View Controller 的方向，所有这些都在代码中，但我无法根据 View Controller 中的内容将单元格设置为自身大小，任何帮助将不胜感激？ p>

这是表格 View 单元格的相关代码:

final class ViewControllerContainedTableViewCell: UITableViewCell {

    private lazy var contentViewController: UIViewController = {
        let viewController = UIViewController()
        viewController.view.translatesAutoresizingMaskIntoConstraints = false
        return viewController
    }()

    func addContentViewController(parent: UIViewController?) {
        contentViewController.willMove(toParent: parent)
        parent?.addChild(contentViewController)
        contentView.addSubview(contentViewController.view)

        NSLayoutConstraint.activate([
            contentViewController.view.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
            contentViewController.view.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
            contentViewController.view.topAnchor.constraint(equalTo: contentView.topAnchor),
            contentViewController.view.bottomAnchor.constraint(equalTo: contentView.bottomAnchor)
            ])

        contentViewController.didMove(toParent: parent)
    }

    func removeContentViewController() {
        contentViewController.willMove(toParent: nil)
        contentViewController.view.removeFromSuperview()
        contentViewController.removeFromParent()
    }

}

我在 func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell) 的数据源中调用 addContentViewController(parent: UIViewController?) 和 removeContentViewController() 、 forRowAt indexPath: IndexPath) 和 func tableView(_ tableView: UITableView, didEndDisplaying cell: UITableViewCell, forRowAt indexPath: IndexPath) 分别。

这是 View Controller 的相关代码(示例):

final class ContentViewController: UIViewController {

    private let titleLabel: UILabel = {
        let label = UILabel()
        label.text = "Title"
        label.translatesAutoresizingMaskIntoConstraints = false
        return label
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        setupLayout()
    }

    private func setupLayout() {
        view.addSubview(titleLabel)

        NSLayoutConstraint.activate([
            titleLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            titleLabel.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            titleLabel.topAnchor.constraint(equalTo: view.topAnchor),
            titleLabel.bottomAnchor.constraint(equalTo: view.bottomAnchor)
            ])
    }

}

我希望我的单元格能够自行调整大小以适合标题标签，但单元格仍然保持 44pt 高度。

您可以提供任何帮助或指导吗？我是否正确使用/嵌入了 View Controller ？我做错了什么？

提前致谢!

Answer 1

所以我尝试了你的示例并对其进行了一些编辑以使 View Controller 能够工作。您的设置似乎工作正常。

以下是完整代码，您可以将其粘贴到新项目“ViewController.swift”中。 Storyboard中添加了表格 View ，并设置了具有委托(delegate)的数据源。

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    @IBOutlet private var tableView: UITableView?

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 100
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = ViewControllerContainedTableViewCell()
        cell.parentViewController = self
        cell.setContentViewController(controller: {
            let controller = ContentViewController()
            controller.view.translatesAutoresizingMaskIntoConstraints = false
            if indexPath.row%2 == 0 {
                controller.text = "Some fairly long text to get a bit of a feeling as to what is going on here"
                controller.view.backgroundColor = UIColor.black.withAlphaComponent(0.2)
            } else {
                controller.text = "Some fairly long text to get a bit of a feeling as to what is going on here Some fairly long text to get a bit of a feeling as to what is going on here Some fairly long text to get a bit of a feeling as to what is going on here Some fairly long text to get a bit of a feeling as to what is going on here"
            }
            return controller
        }())
        return cell
    }

}

final class ViewControllerContainedTableViewCell: UITableViewCell {

    var parentViewController: UIViewController?
    var childViewController: UIViewController?


    func setContentViewController(controller: UIViewController?) {
        guard let parentViewController = parentViewController else {
            print("No parent controller set!")
            return
        }

        removeContentViewController()
        childViewController = controller

        if let controller = controller {
            controller.willMove(toParent: parentViewController)
            parentViewController.addChild(controller)
            contentView.addSubview(controller.view)

            NSLayoutConstraint.activate([
                controller.view.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
                controller.view.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
                controller.view.topAnchor.constraint(equalTo: contentView.topAnchor),
                controller.view.bottomAnchor.constraint(equalTo: contentView.bottomAnchor)
                ])

            controller.didMove(toParent: parentViewController)
        }


    }

    func removeContentViewController() {
        guard let childViewController = childViewController else { return }
        childViewController.willMove(toParent: nil)
        childViewController.view.removeFromSuperview()
        childViewController.removeFromParent()
    }

}

final class ContentViewController: UIViewController {

    private let titleLabel: UILabel = {
        let label = UILabel()
        label.numberOfLines = 0
        label.text = "Title"
        label.translatesAutoresizingMaskIntoConstraints = false
        return label
    }()

    var text: String? {
        didSet {
            titleLabel.text = text
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        setupLayout()
        titleLabel.text = self.text
    }

    private func setupLayout() {
        view.addSubview(titleLabel)

        NSLayoutConstraint.activate([
            titleLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            titleLabel.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            titleLabel.topAnchor.constraint(equalTo: view.topAnchor),
            titleLabel.bottomAnchor.constraint(equalTo: view.bottomAnchor)
            ])
    }

}

这是结果: