Como obter corretamente o conteúdo do tableViewCell'sViewView bound size?

Recursos

Li várias respostas deUsar o layout automático no UITableView para layouts de células dinâmicos e alturas de linhas variáveis

E seguiu as sugestões deles, mas não está funcionand

Configuração para reproduzir:

Se você copiar / colar oMyTableViewCell eViewController snippets: então você pode reproduzir o problem

Subclassifiquei MyTableViewCell e adicionei meu próprio rótul

    import UIKit

    class MyTableViewCell: UITableViewCell {

        lazy var customLabel : UILabel = {
            let lbl = UILabel()
            lbl.translatesAutoresizingMaskIntoConstraints = false
            lbl.numberOfLines = 0
            return lbl
        }()

        override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
            super.init(style: style, reuseIdentifier: reuseIdentifier)
            setupLayout()
        }
        private func setupLayout(){
            contentView.addSubview(customLabel)

            let top = customLabel.topAnchor.constraint(equalTo: contentView.topAnchor)
            let bottom = customLabel.bottomAnchor.constraint(equalTo: contentView.bottomAnchor)
            let leadingFromImage = customLabel.leadingAnchor.constraint(equalTo: imageView!.trailingAnchor, constant: 5)
            let trailing = customLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor)

            NSLayoutConstraint.activate([top, bottom, leadingFromImage, trailing])
        }

        required init?(coder aDecoder: NSCoder) {
            fatalError()
        }
    }

Os seguintesViewController contém minha tableview:

import UIKit

class ViewController: UIViewController {

    var datasource = ["It would have been a great day had Manchester United Lost its \n game. Anyhow I hope tomorrow Arsenal will win the game"]

    lazy var tableView : UITableView = {
        let table = UITableView()
        table.delegate = self
        table.dataSource = self
        table.translatesAutoresizingMaskIntoConstraints = false
        table.estimatedRowHeight = 100
        table.rowHeight = UITableViewAutomaticDimension
        return table
    }()
    override func viewDidLoad() {
        super.viewDidLoad()
        view.addSubview(tableView)
        tableView.pinToAllEdges(of: view)
        tableView.register(MyTableViewCell.self, forCellReuseIdentifier: "id")
    }
}

extension ViewController: UITableViewDelegate, UITableViewDataSource {

    func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

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

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "id", for: indexPath) as! MyTableViewCell

        cell.customLabel.text = datasource[indexPath.row]
        logInfo(of: cell)

        cell.accessoryType = .detailDisclosureButton
        cell.imageView?.image = UIImage(named: "honey")
        cell.layoutSubviews()
        cell.customLabel.preferredMaxLayoutWidth = tableView.bounds.width
        logInfo(of: cell)
        print("---------")

        return cell
    }

    private func logInfo(of cell: MyTableViewCell){
        print("boundsWidth: \(cell.contentView.bounds.width) | maxLayoutWidth: \(cell.contentView.bounds.width - 44 - 15 - 5) | systemLayoutSizeFitting : \(cell.customLabel.systemLayoutSizeFitting(UILayoutFittingCompressedSize))")
    }    
}

extension UIView{

    func pinToAllEdges(of view: UIView){
        let leading = leadingAnchor.constraint(equalTo: view.leadingAnchor)
        let top = topAnchor.constraint(equalTo: view.topAnchor)
        let trailing = trailingAnchor.constraint(equalTo: view.trailingAnchor)
        let bottom = bottomAnchor.constraint(equalTo: view.bottomAnchor)        

        NSLayoutConstraint.activate([leading, top, trailing, bottom])
    }
}

Link parahoney image Eu usei. Eu configurei o tamanho para44 * 44

Problema principa

Meu grande problema está dentrocellForRowAtIndex:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "id", for: indexPath) as! MyTableViewCell

    cell.customLabel.text = datasource[indexPath.row]
    logInfo(of: cell)

    cell.accessoryType = .detailDisclosureButton
    cell.imageView?.image = UIImage(named: "honey")
    cell.layoutSubviews()
    cell.customLabel.preferredMaxLayoutWidth = cell.contentView.bounds.width
    logInfo(of: cell)
    print("---------")

    return cell
}

Questões

Por qualquer motivo, o valor atribuído a:

cell.customLabel.preferredMaxLayoutWidth

parece não estar certo.

Q1: Por que é que

Q2: Estou registrando o limite do contentView antes e depois de ligar paracell.layoutSubviews e muda de320 para260 mas, eventualmente, no viewDebugger, ele aparece como308 !!!

Por que os limites do contenView estão mudando novamente?!

Eu removi outras capturas de tela da pergunta. Eles eram principalmente desorganizados, mas talvez valessem a pena procurar. Você pode dar uma olhada no histórico de revisões.

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