从Swift中的另一个类访问某些值

时间:2017-07-26 16:29:25

标签: ios swift uitableview

我有一个像这样的TableViewCell类:

class CampaignsTableViewCell: UITableViewCell {

    @IBOutlet weak var activateButton: UIButton!
    @IBOutlet weak var titleCampaignPlaceholder: UILabel!

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
        setUpButton()
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)
        // Configure the view for the selected state
    }

    private func setUpButton(){
        activateButton.backgroundColor = .clear
        activateButton.layer.cornerRadius = 5
        activateButton.layer.borderWidth = 1
        activateButton.layer.borderColor = UIColor.blue.cgColor
    }
}

而且,在另一个ViewController类我有我的UITableView方法:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let rowNumber = indexPath.row
    let cellIdentifier = "CampaignTableViewCell"
    guard let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as? CampaignsTableViewCell else {
        fatalError("The dequeued cell is not an instance of TableViewCellController.")
    }

    cell.titleCampaignPlaceholder.text = campaignsArray[rowNumber].campaignName


    return cell
}

我需要在我的UITableView方法中使用我的activateButton才能访问campaignsArray。我有另一个方法来从该数组中取消值,所以每次从UITableView按下activateButton时我都需要调用该方法。

有什么想法吗? 非常感谢你

2 个答案:

答案 0 :(得分:3)

在UITableViewCell中有按钮的情况下,我喜欢做的事情如下:

为单元格提供一个闭包,当按下按钮时调用该闭包

class CampaignsTableViewCell: UITableViewCell {
   ... all your code....

   // give your cell a closure that is called when the button is pressed    
   var onButtonPressed: ((_ sender: UIButton) -> ())?

   @IBAction func buttonPressed(sender: UIButton) {  // wire that one up in IB
       onButtonPressed?(sender)
   }
 }

然后在你的TableViewController

let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as! CampaignsTableViewCell

cell.titleCampaignPlaceholder.text = campaignsArray[rowNumber].campaignName

cell.onButtonPressed = { [weak self] sender in
    // Do your magic stuff here
}

return cell

希望有所帮助

答案 1 :(得分:3)

您的手机将获得该事件,而不是tableView。你需要做的是:

在您的单元格内创建协议:

protocol CampaignsTableViewProtocol{
    func actionButtonPressed(row: Int)
}

class CampaignsTableViewCell: UITableViewCell {

    @IBOutlet weak var activateButton: UIButton!
    @IBOutlet weak var titleCampaignPlaceholder: UILabel!
    // keep info about row 
    var rowIndex: Int = -1
    // create delegate that will let your tableView about action button in particular row
    var delegate : CampaignsTableViewProtocol?

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
        setUpButton()
        self. activateButton.addTarget(self, action: #selector(self.activatePressed), for: UIControlEvents.touchDown)
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)
        // Configure the view for the selected state
    }

    func activatePressed(){
         self.delegate?.actionButtonPressed(row :rowIndex)
    }

    private func setUpButton(){
        activateButton.backgroundColor = .clear
        activateButton.layer.cornerRadius = 5
        activateButton.layer.borderWidth = 1
        activateButton.layer.borderColor = UIColor.blue.cgColor
    }
}

你的tableViewController需要采用这个协议:

class MyTableViewController: UITableViewDelegate, UITableViewDataSource, CampaignsTableViewProtocol {
// rest of the code
}

此外,您需要在tableViewController中实现委托函数:

func actionButtonPressed(row: Int) {
    // get campaign you need
    let campaign = campaignsArray[row]
    // rest of the code
}