滑动以删除UICollectionView无法正常工作

Question

我正在尝试按照这篇文章的教程：How to implement UITableView`s swipe to delete for UICollectionView完全一样，除了从故事板添加插件外，我已经以编程方式初始化了所有内容（包括我的集合视图）。

当我到达包含集合视图的屏幕时，不会显示用于显示其下方删除按钮的滑动操作。我已设置委托方法shouldRecognizeSimultaneouslyWith返回true并设置了单元格如下：

import UIKit

class CustomCollectionViewCell: UICollectionViewCell {

    // Cell data
    var aLabel       : UILabel!
    var bLabel       : UILabel!
    var myImageView  : UIImageView!
    var myContentView: UIView!

    // Swipe to delete cell
    var contentViewLeftConstraint             : NSLayoutConstraint!
    var contentViewRightConstraint            : NSLayoutConstraint!
    var deleteButton                          : UIButton!
    var startPoint                            = CGPoint()
    var startingRightLayoutConstraintConstant = CGFloat()
    var swipeView                             : UIView!

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

        backgroundColor = .clear

        myImageView = UIImageView(frame: CGRect(
            x     : 15,
            y     : 10,
            width : frame.height - 20,
            height: frame.height - 20
        ))

        aLabel = UILabel(frame: CGRect(
            x     : myImageView.frame.maxX + 15,
            y     : 15,
            width : frame.width - 20 - myImageView.frame.maxX,
            height: 23
        ))

        bLabel = UILabel(frame: CGRect(
            x     : myImageView.frame.maxX + 15,
            y     : aLabel.frame.maxY,
            width : frame.width - 20 - myImageView.frame.maxX,
            height: 30
        ))

        swipeView = UIView(frame: CGRect(
            x     : contentView.frame.width - 60,
            y     : contentView.frame.minY,
            width : 60,
            height: contentView.frame.height
        ))
        deleteButton = UIButton(frame: swipeView.frame)
        deleteButton.backgroundColor = .red  // For visibility purposes
        swipeView.addSubview(deleteButton)

        myContentView = UIView(frame: contentView.frame)
        myContentView.addSubview(myImageView)
        myContentView.addSubview(aLabel)
        myContentView.addSubview(bLabel)

        contentView.addSubview(swipeView)
        contentView.addSubview(myContentView)

        // Pin the song data content view's left margin to the cell content view's left margin.
        contentViewLeftConstraint  = NSLayoutConstraint(
            item      : myContentView,
            attribute : .left,
            relatedBy : .equal,
            toItem    : contentView,
            attribute : .leftMargin,
            multiplier: 1.0,
            constant  : 0.0
        )
        contentViewLeftConstraint.isActive = true

        // Pin the song data content view's right margin to the cell content view's right margin.
        contentViewRightConstraint = NSLayoutConstraint(
            item      : myContentView,
            attribute : .right,
            relatedBy : .equal,
            toItem    : contentView,
            attribute : .rightMargin,
            multiplier: 1.0,
            constant  : 0.0
        )
        contentViewRightConstraint.isActive = true
    }
}

我的ViewController方法与教程中的方法完全相同。我在Ray Wenderlich的原始教程中打印出平移动作，并且平移手势表现得如预期的那样。只是myContentView向左滑动以显示删除按钮。也许我错误地设置了约束？

请帮忙！