Question

我将集合视图单元重用为自定义单选按钮。作为单选按钮选择，我使用两个视图：

边框视图
标记视图

标记视图已隐藏并缩放。它基本上是简单的选择。

在RadioButtonCollectionViewCell：

var checkMark: UIView = {
    let view = UIView()
    view.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
    view.backgroundColor = .darkGreyFts
    view.translatesAutoresizingMaskIntoConstraints = false
    return view
}()

override var isSelected: Bool {
    get {
        return super.isSelected
    } set {
        super.isSelected = newValue
        isSelected ? checkMark.scaleAnimate(1) :     checkMark.scaleAnimate(-1)
    }
}

override func prepareForReuse() {
    super.prepareForReuse()
    self.infoLabel.text = nil
    self.checkMark.isHidden = false
}

UIView扩展名：

  func scaleAnimate(_ state: Int) {
        switch state {
        case 1:
            self.isHidden = false
            UIView.animate(withDuration: 0.3, delay: 0, options: .curveEaseOut, animations: {
                self.transform = CGAffineTransform(scaleX: 1, y: 1)
            })
        case -1:
            UIView.animate(withDuration: 0.3, delay: 0, options: .curveEaseOut, animations: {
                self.transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
            }, completion: { _ in
                self.isHidden = true
            })
        default:
            break
        }
    }

// MARK: - UICollectionView delegate.

extension DriverFormsViewController : UICollectionViewDelegate {

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        if let cell = collectionView.cellForItem(at: indexPath) as? RadioButtonCollectionViewCell {
            cell.isSelected = true
            collectionCellSelectedAtIndexPath = indexPath
        }

    }

    func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
        if let cell = collectionView.cellForItem(at: indexPath) as? RadioButtonCollectionViewCell {
            cell.isSelected = false
        }
    }

}

// MARK: - UICollectionView data source.

extension DriverFormsViewController : UICollectionViewDataSource {

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return optionsDictionary.count
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath) as! RadioButtonCollectionViewCell
        let key = optionsKeys[indexPath.row]

        cell.infoLabel.text = optionsDictionary[key]
        cell.checkMark.isHidden = true
        if let collectionCellIsSelectedAtIndexPath = collectionCellSelectedAtIndexPath {
            if collectionCellIsSelectedAtIndexPath == indexPath {
                cell.checkMark.scaleAnimate(1)
            }
        }
        return cell
    }
}

我如何能够重用隐藏/未缩放的视图？每当我向下滚动并返回到集合时，选择的单元格未被选中 - 意味着，复选标记被隐藏，每当我点击此单元格时，它都没有动画。什么想法可能是错的？

提前致谢！

Answer 1

您必须确保在选择新单元格之前取消选择当前单元格

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    if let currentSelectedIndexPath = collectionCellSelectedAtIndexPath, 
       let currentCell = cellForItem(at: currentSelectedIndexPath) as? RadioButtonCollectionViewCell {
       currentCell.isSelected = false
    }
    if let cell = collectionView.cellForItem(at: indexPath) as? RadioButtonCollectionViewCell {
        cell.isSelected = true
        collectionCellSelectedAtIndexPath = indexPath
    }
}

而不是使用prepareForReuse我会在else

中添加cellForItemAt子句

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath) as! RadioButtonCollectionViewCell
    let key = optionsKeys[indexPath.row]

    cell.infoLabel.text = optionsDictionary[key]
    cell.checkMark.isHidden = true
    if let collectionCellIsSelectedAtIndexPath = collectionCellSelectedAtIndexPath, 
       collectionCellIsSelectedAtIndexPath == indexPath {
          cell.checkMark.scaleAnimate(1)
    } else {
          cell.checkMark.scaleAnimate(-1)
    }
    return cell
}

重用具有隐藏/缩放组件的单元格

1 个答案: