Stepper on tableview cell (swift)

问题:

I put stepper both outlets and action into tableview cell and using protocol delegate to connect it to tableview. When i tapped stepper in first row, stepper value appear normaly in first row but its also appear in some random row. how to fix this?

TableViewCell

protocol ReviewCellDelegate{
    func stepperButton(sender: ReviewTableViewCell)
}

class ReviewTableViewCell: UITableViewCell {
   @IBOutlet weak var countStepper: UIStepper!
   @IBOutlet weak var stepperLabel: UILabel!

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

override func setSelected(selected: Bool, animated: Bool) {
    super.setSelected(selected, animated: animated)

    // Configure the view for the selected state
}

@IBAction func stepperButtonTapped(sender: UIStepper) {
    if delegate != nil {
        delegate?.stepperButton(self)
        stepperLabel.text = "x \(Int(countStepper.value))"

    }
}

ViewController

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cellIdentifier = "reviewCell"
    let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier, forIndexPath: indexPath) as! ReviewTableViewCell


    var imageView: UIImageView?
    let photoG = self.photos[indexPath.row]
    imageView = cell.contentView.viewWithTag(1) as? UIImageView
    //let layout = cell.goodiesImage
    let tag = indexPath.row // +1
    cell.tag = tag
    photoG.fetchImageWithSize(CGSize(width: 1000, height: 1000), completeBlock: { image, info in
        if cell.tag == tag {
            imageView?.image = image
            cell.goodiesImage.image = image
        }
    })

func stepperButton(sender: ReviewTableViewCell) {
    if let indexPath = tableView.indexPathForCell(sender){
        print(indexPath)
    }
}

回答1:

As mentioned by @A-Live, your component is being reused and so need to be updated.

So in your view controller:

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cellIdentifier = "reviewCell"
    let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier, forIndexPath: indexPath) as! ReviewTableViewCell


    var imageView: UIImageView?
    let photoG = self.photos[indexPath.row]
    imageView = cell.contentView.viewWithTag(1) as? UIImageView
    //let layout = cell.goodiesImage
    let tag = indexPath.row // +1
    cell.tag = tag
    photoG.fetchImageWithSize(CGSize(width: 1000, height: 1000), completeBlock: { image, info in
    if cell.tag == tag {
        imageView?.image = image
        cell.goodiesImage.image = image
    }
})
    cell.countStepper.value = XXX[indexPath.row].value; //Here you update your view
    cell.stepperLabel.text = "x \(Int(cell.countStepper.value))" //And here

And

func stepperButton(sender: ReviewTableViewCell) {
    if let indexPath = tableView.indexPathForCell(sender){
        print(indexPath)
        XXX[sender.tag].value = sender.counterStepper.value //Here you save your updated value
}

回答2:

Reset the value of stepper while loading your cell. you can reset the cell property values in cell's prepareForReuse method. add the following method in your ReviewTableViewCell class.

 override func prepareForReuse() 
 {
   super.prepareForReuse()

   countStepper.value = 0.0 
 }

回答3:

In tableViewCell VC:

1 - add these field

var cellDelegate: cellProtocol?
var index: IndexPath?

2 - then add this in the delegate:

func onStepperClick(index: Int, sender: UIStepper)

3 - when you have dragged your stepper over as an action use this:

@IBAction func cellStepper(_ sender: UIStepper) {
    cellDelegate?.onStepperClick(index: (index?.row)!, sender: sender)
    sender.maximumValue = 1  //for incrementing
    sender.minimumValue = -1 //for decrementing
    //this will make sense later
}

In ViewController

1 - add these to the tableView function that has the cellAtRow variable.

cell.cellDelegate = self
cell.index = indexPath 

2 - Use this instead of your stepperButton function

func onStepperClick(index: Int, sender: UIStepper) {
    print(index)

    if sender.value == 1.0{
        //positive side of stepper was pressed
    }else if sender.value == -1.0{
        //negative side of stepper was pressed
    }

    sender.value = 0  //resetting to zero so sender.value produce different values on plus and minus

}

Hope this works for you