Collection view cell content is layering - ios

Question

My button labels are stacked/regenerated when I scroll. So the first label might display Alabel with Elabel on top of it after has left the view and re-entered. I'm simply trying to create a single row of scrollable buttons (or labels for that matter). The collection view and cell were created via Storyboard. The code generates the correct number of cells in the CV, but the labels become layered when scrolled (horizontal).
let buttonLabels = ["Alabel", "Blabel", "Clabel", "Dlabel", "Elabel", "Flabel", "Glabel", "Hlabel", "Ilabel", "Jlabel", "Klabel", "Llabel", "Mlabel"]
#IBOutlet weak var btnCollVw: UICollectionView!
//loadColFlowLayout() is called from ViewDidLoad()
func loadColFlowLayout() {
let btnLayout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
btnLayout.scrollDirection = UICollectionViewScrollDirection.Horizontal
btnLayout.sectionInset = UIEdgeInsets(top: 0, left: 1, bottom: 0, right: 1)
btnLayout.itemSize = CGSize(width: 63, height: 30)
btnCollVw.collectionViewLayout = btnLayout
btnCollVw!.backgroundColor = UIColor.whiteColor()
}
func numberOfSections() -> Int {
return 1
}
func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return buttonLabels.count
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
var cell: UICollectionViewCell = self.iconCollVw.dequeueReusableCellWithReuseIdentifier("swIconsCell", forIndexPath: indexPath) as UICollectionViewCell
var makeButton = UIButton(frame: CGRectMake(0, 0, 63, 29))
makeButton.setTitle(buttonLabels[indexPath.item], forState: .Normal)
makeButton.setTitleColor(UIColor.blackColor(), forState: .Normal)
cell.addSubview(makeButton)
// or using cell.contentView.addSubview(makeButton)
return cell
}
}

Answer 1

the problem in cell reusing, each time when you dequeue cell from collection view it can already has button, look at my a bit improved version when I check for button with known tag on cell:
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
var cell: UICollectionViewCell = collectionView.dequeueReusableCellWithReuseIdentifier("swIconsCell", forIndexPath: indexPath) as UICollectionViewCell
if cell.viewWithTag(1234) == nil {
var makeButton = UIButton(frame: CGRectMake(0, 0, 63, 29))
makeButton.setTitle(buttonLabels[indexPath.item], forState: .Normal)
makeButton.setTitleColor(UIColor.blackColor(), forState: .Normal)
makeButton.tag = 1234;
cell.addSubview(makeButton)
// or using cell.contentView.addSubview(makeButton)
}
return cell
}
you can do the same in another way for example create subclass of UICollectionViewCell