UICollectionViewCell 问题中的 UISwipeGestureRecogniser

Question

我有一个 UICollectionView，其中每个单元格都有一个左右 UISwipeGestureRecognizer，这给人一种翻转菜单图像的错觉。我不知道该怎么做的是 "closing/flipping" 在翻转另一个单元格之前先翻转了单元格。

这是现在的屏幕截图：

class Note: UICollectionViewCell {
var isFlipped = false

func addSwipeGestures() {
    let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(swipeLeft(swipe:)))
    swipeLeft.direction = UISwipeGestureRecognizer.Direction.left
    contentView.addGestureRecognizer(swipeLeft)

    let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(swipeRight(swipe:)))
    swipeRight.direction = UISwipeGestureRecognizer.Direction.right
    contentView.addGestureRecognizer(swipeRight)
}

@objc func swipeLeft(swipe: UISwipeGestureRecognizer) {
    if isFlipped {
        flipToBackView(options: .transitionFlipFromLeft)
    }
    else {
        flipToFrontView(options: .transitionFlipFromLeft)
    }
}

@objc func swipeRight(swipe: UISwipeGestureRecognizer) {
    if isFlipped {
        flipToBackView(options: .transitionFlipFromRight)
    }
    else {
        flipToFrontView(options: .transitionFlipFromRight)
    }
}

func flipToBackView(options: UIView.AnimationOptions ) {
    UIView.transition(with: backView, duration: 0.3, options: options, animations: { [unowned self] in
        self.coverImageView.isHidden = false
        self.titleLabel.isHidden = false
        self.titleView.isHidden = false
        self.isFlipped = !self.isFlipped
    })
}

func flipToFrontView(options: UIView.AnimationOptions) {
    UIView.transition(with: backView, duration: 0.3, options: options, animations: { [unowned self] in
        self.coverImageView.isHidden = true
        self.titleLabel.isHidden = true
        self.titleView.isHidden = true
        self.isFlipped = !self.isFlipped
    })
}
}

Answer 1

您可以为此使用 delegation pattern。例如。您可以在注释 class:

中添加一个协议

protocol FlipDelegate: class {
    func willFlip(note: Note)
}

让ViewController符合这个协议，存储最后一张翻转的牌的引用，然后再次翻转最后一张翻转的牌：

    weak var lastFlippedNote: Note?

    func willFlip(_ note: Note) {
        lastFlippedNote?. flipToBackView(options: .transitionFlipFromLeft)
        lastFlippedNote = note

    }

添加对注释 class 的弱引用，例如 weak var flipDelegate: FlipDelegate?，并将 viewController 分配给 collectionView(_:cellForItemAt:) 中的单元格。在您的滑动操作中，您可以调用 willFlip(_:) 例如当您翻到笔记的正面时，例如：

@objc func swipeLeft(swipe: UISwipeGestureRecognizer) {
    if isFlipped {
        flipToBackView(options: .transitionFlipFromLeft)
    }
    else {
        flipToFrontView(options: .transitionFlipFromLeft)
        flipDelegate?.willFlip(note: self)
    }
}

@objc func swipeRight(swipe: UISwipeGestureRecognizer) {
    if isFlipped {
        flipToBackView(options: .transitionFlipFromRight)
    }
    else {
        flipToFrontView(options: .transitionFlipFromRight)
        flipDelegate?.willFlip(note: self)
    }
}

此致

UICollectionViewCell 问题中的 UISwipeGestureRecogniser

UISwipeGestureRecogniser in UICollectionViewCell issue

ios

uiswipegesturerecognizer

uicollectionviewcell

swift