ios - UICollectionview 重新排序图像单元格

Question

我有一个带有 XX 个图像/单元格的 UICollectionview，我想让它们在拖放时交换位置。我正在使用内置的重新排序功能，但它不能满足我的需求。这是代码:

longPressGesture = UILongPressGestureRecognizer(target: self, action: #selector(handleLongGesture))
        longPressGesture.minimumPressDuration = 0.2
        longPressGesture.delaysTouchesBegan = true

        cameraRollCollectionView.addGestureRecognizer(longPressGesture)

func handleLongGesture(gesture: UILongPressGestureRecognizer) {

        switch(gesture.state) {

        case UIGestureRecognizerState.began:
            guard let selectedIndexPath = cameraRollCollectionView.indexPathForItem(at: gesture.location(in: cameraRollCollectionView)) else {
                break
            }
            cameraRollCollectionView.beginInteractiveMovementForItem(at: selectedIndexPath)
        case UIGestureRecognizerState.changed:
            cameraRollCollectionView.updateInteractiveMovementTargetPosition(gesture.location(in: gesture.view!))
        case UIGestureRecognizerState.ended:
            cameraRollCollectionView.endInteractiveMovement()
        default:
            cameraRollCollectionView.cancelInteractiveMovement()
        }
    }

我基本上只是希望动画仅交换移动单元格和目标单元格，而不是像所附图像那样对“邻居”重新排序。

我用下面的代码让它在“后面”工作:

func collectionView(_ collectionView: UICollectionView,
                        moveItemAt sourceIndexPath: IndexPath,
                        to destinationIndexPath: IndexPath) {


        let temp = selectedUIImages[sourceIndexPath.row]
        selectedUIImages[sourceIndexPath.row] = selectedUIImages[destinationIndexPath.row]
        selectedUIImages[destinationIndexPath.row] = temp
 }

Answer 1

当您识别出长按某个单元格时，您可以创建 collectionViewCell 的 contentView 的副本。然后，您可以使该副本随着触摸而移动(touchesMoved)，同时所有单元格都静止，并且当用户放下它(touchesEnded)时，您可以计算该位置的indexPath。当您拥有indexPath 时，您可以像已经做的那样更改位置。