Swift bool数据未传递到TableView单元格

Question

I have a tableview that gets the data from an API. There is a isUnlocked variable that is also getting value from the API. But besides the title and picture, the isUnlocked variable still has the default value set in the custom tableview class.

I pass the value in cellForRow function like this:

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
}

And this is the custom class for tableview cell:

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)

}

The isUnlocked variable has the default False value no matter what I set it in the cellForRow function. Guys it's killing me please help.

Answer 1

I think your value is being set, but your UI is not being updated because it only gets set during initialization, where obviously the value of the Bool will always be the default value (false). So instead of calling setUpUI() in init() , call it after dequeue-ing.

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
}

Or atleast move the set up of courseButton2 to another method and call that method.

Answer 2

Problem solved by adding this block of code:

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

Just add this code to the cell, and your ok to go!