Question

我有一个从API获取数据的表格视图。有一个 isUnlocked 变量也从API中获得价值。但是除了标题和图片之外， isUnlocked 变量仍具有在自定义tableview类中设置的默认值。

我像这样在cellForRow函数中传递值：

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    var cell = UITableViewCell()
    if tableView.tag == 1 {
        let c = tableView.dequeueReusableCell(withIdentifier: CourseViewIdentifiers.courses.rawValue, for: indexPath) as! CourseViewTableViewCell
        c.isUnlocked = tableData[indexPath.row].unlocked
        c.selectionStyle = .none
        c.courseTitle.text = tableData[indexPath.row].title
        c.courseImage.loadImageFrom(urlString: tableData[indexPath.row].pic)
        cell = c
    }
    return cell
}

这是tableview单元格的自定义类：

public var isUnlocked: Bool = false

private lazy var backView: UIView = {
    let view = UIView()
    view.backgroundColor = UIColor.lightGray.withAlphaComponent(0.2)
    view.layer.cornerRadius = 5
    view.layer.borderColor = UIColor.lightGray.cgColor
    view.layer.borderWidth = 0.5
    return view
}()

public lazy var courseImage: WebImageloader = {
    let imv = WebImageloader()
    imv.contentMode = .scaleAspectFill
    return imv
}()

public lazy var courseTitle: UILabel = {
    let label = UILabel()
    label.font = UIFont.iransans(size: 18)
    label.textAlignment = .right
    return label
}()

private lazy var courseButton1: UIButton = {
    let button = UIButton(type: .system)
    if !isUnlocked {
        button.setBackgroundImage(#imageLiteral(resourceName: "locked"), for: .normal)
        button.isEnabled = false
    }else{
        button.setBackgroundImage(#imageLiteral(resourceName: "play"), for: .normal)
    }
    return button
}()

private lazy var courseButton2: UIButton = {
    let button = UIButton(type: .system)
    button.setBackgroundImage(#imageLiteral(resourceName: "download"), for: .normal)
    return button
}()

override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
    super.init(style: .default, reuseIdentifier: CourseViewIdentifiers.courses.rawValue)
    print(isUnlocked,"***************")
    setupUI()
    contentView.backgroundColor = .clear
}

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

private func setupUI() {

    backView.translatesAutoresizingMaskIntoConstraints = false
    contentView.addSubview(backView)
    backView.topAnchor.constraint(equalTo: contentView.topAnchor, constant: 15).isActive = true
    backView.centerXAnchor.constraint(equalTo: centerXAnchor).isActive = true
    backView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 5).isActive = true
    backView.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -5).isActive = true
    backView.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: -5).isActive = true

    courseImage.translatesAutoresizingMaskIntoConstraints = false
    backView.addSubview(courseImage)
    courseImage.rightAnchor.constraint(equalTo: backView.rightAnchor, constant: -10).isActive = true
    courseImage.centerYAnchor.constraint(equalTo: backView.centerYAnchor).isActive = true
    courseImage.heightAnchor.constraint(equalToConstant: 50).isActive = true
    courseImage.widthAnchor.constraint(equalToConstant: 50).isActive = true
    courseImage.layer.cornerRadius = 25
    courseImage.clipsToBounds = true

    courseButton1.translatesAutoresizingMaskIntoConstraints = false
    backView.addSubview(courseButton1)
    courseButton1.leftAnchor.constraint(equalTo: backView.leftAnchor, constant: 10).isActive = true
    courseButton1.centerYAnchor.constraint(equalTo: backView.centerYAnchor).isActive = true
    courseButton1.heightAnchor.constraint(equalToConstant: 30).isActive = true
    courseButton1.widthAnchor.constraint(equalToConstant: 30).isActive = true
    courseButton1.layer.cornerRadius = 15
    courseButton1.clipsToBounds = true

    if isUnlocked {
        courseButton2.translatesAutoresizingMaskIntoConstraints = false
        backView.addSubview(courseButton2)
        courseButton2.leftAnchor.constraint(equalTo: courseButton1.rightAnchor, constant: 10).isActive = true
        courseButton2.centerYAnchor.constraint(equalTo: backView.centerYAnchor).isActive = true
        courseButton2.heightAnchor.constraint(equalToConstant: 30).isActive = true
        courseButton2.widthAnchor.constraint(equalToConstant: 30).isActive = true
        courseButton2.layer.cornerRadius = 15
        courseButton2.clipsToBounds = true
    }

    courseTitle.translatesAutoresizingMaskIntoConstraints = false
    backView.addSubview(courseTitle)
    courseTitle.rightAnchor.constraint(equalTo: courseImage.leftAnchor, constant: -10).isActive = true
    courseTitle.topAnchor.constraint(equalTo: courseImage.topAnchor).isActive = true
    courseTitle.leftAnchor.constraint(equalTo: courseButton1.rightAnchor, constant: 10)

}

无论我在cellForRow函数中设置了什么，isUnlocked变量都具有默认的False值。伙计们，这杀了我，请帮忙。

Answer 1

我认为您的值已设置，但您的UI尚未更新，因为它仅在初始化期间设置，显然Bool的值始终是默认值（false）。因此，与其在setUpUI()中调用init()，而在出队后再调用它。

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    var cell = UITableViewCell()
    if tableView.tag == 1 {
        let c = tableView.dequeueReusableCell(withIdentifier: CourseViewIdentifiers.courses.rawValue, for: indexPath) as! CourseViewTableViewCell
        c.isUnlocked = tableData[indexPath.row].unlocked
        c.selectionStyle = .none
        c.courseTitle.text = tableData[indexPath.row].title
        c.courseImage.loadImageFrom(urlString: tableData[indexPath.row].pic)
        c.setUpUI()
        //print(c.isUnlocked)
        cell = c
    }
    return cell
}

或者至少将courseButton2的设置移至另一个方法并调用该方法。

Answer 2

通过添加以下代码块来解决问题：

DispatchQueue.main.async {
        if DownloadManager.isDownloading(url: self.course_url!) {
            self.courseButton2.alpha = 0.5
            self.courseButton2.isEnabled = false
        }
    }

只需将此代码添加到单元格中，就可以了！

Swift bool数据未传递到TableView单元格

2 个答案: