UICollectionViewCell中没有出现多个按钮

Question

I am attempting to programmatically create a button in each cell of a UICollectionView; however, only the first button is visible. I have tried adding print statements to see what subviews my cells have and the button is present but it is not appearing on the screen.

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath)
    // Configure the cell

    let button = UIButton(frame: cell.frame)
    button.addTarget(self, action: #selector(cellClicked), for: UIControlEvents.touchUpInside)
    button.backgroundColor = UIColor.red
    button.tag = indexPath.row
    cell.addSubview(button)

    print(cell.subviews)

    return cell
}

Also, I added a print statement when clicking the buttons and only the first button shows up and prints out 0.

@IBAction func cellClicked(sender: UIButton) {
    print(sender.tag)
}

Here is a screenshot of the collection view, there should be two buttons in the picture but only one appears

Any help is much appreciated.

Answer 1

It's very bad to add button in data source, because when cell reused, new buttons will be created. If you're using Interface Builder, please add button directly. And you can adjust their properties. You can also define a custom cell, and just CTRL-Drag an outlet. Or handle selection in collection view's delegate.

optional public func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath)

Another solution is add button in cell's awakeFromNib() , this will be called only once.