Swift 2-performBatchUpdates-在UICollectionView框架内可见时，对单元格进行逐一动画处理 [英] Swift 2 - performBatchUpdates - Animate cell one by one when visibile inside the UICollectionView frame

问题描述

我正在尝试为框架中的 UICollectionView 可见的每个单元设置动画。
每次滚动新的单元格时都会显示动画。

I am trying to animate each cell of my UICollectionView visibile in the frame. Every time I scroll a new cell appears with the animation.

我正在使用 performBatchUpdates 在 cellForItemAtIndexPath 内部，动画将同时应用于所有单元，而且速度非常快。似乎无法识别1秒的动画。

I am doing this using performBatchUpdates inside cellForItemAtIndexPath however, the animation is applied to all cells at the same time and its very fast. It seems that the animation of 1 second its not recognised.

我还试图找到一种方法，当不成功按下按钮时将动画应用于单元格

Also I am trying to find the way to apply an animation to a cell when a button is pressed with no success.

我使用的代码是：

override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
{
    let Cell = collectionView.dequeueReusableCellWithReuseIdentifier("Cell", forIndexPath: indexPath) as! CellClass

    self.collectionView?.performBatchUpdates({
                        Cell.layer.cornerRadius = 200
                        return
                        }){
                            completed in

                            UIView.animateWithDuration(1, animations: {
                                Cell.layer.cornerRadius = 0
                            })
                        }

    Cell.playAnimationBtn.layer.setValue(indexPath.row, forKey: "indexPlayBtn")
}

@IBAction func actionGetAnimation(sender: UIButton)
{
    let indexUser = (sender.layer.valueForKey("indexPlayBtn")) as! Int

    //Cell selected do animation corners = 200
}

推荐答案

将动画移动到 willDisplayCell（_：cell：indexPath：）时，您可以使其工作。每次将要显示新单元格时都会调用该方法。

You can make this work when you move the animation to willDisplayCell(_:cell:indexPath:). That method is called every time a new cell is about to be displayed.

您不能将 UIView.animateWithDuration 用于图层属性。为此，您必须使用 CABasicAnimation 。

You cannot use UIView.animateWithDuration for the layer properties. You have to use CABasicAnimation for that.

如果您想在用户按下按钮时对单元进行动画处理，可以从下面的代码示例中调用 animateCellAtIndexPath 。您必须知道单元格的indexPath才能这样做。在此示例中，当用户选择单元格时，我将调用此方法。

If you want to animate the cell when the user presses a button you can call animateCellAtIndexPath from the code example below. You have to know the cell's indexPath to do so. In this example I call this method when the user selects the cell.

func collectionView(collectionView: UICollectionView, willDisplayCell cell: UICollectionViewCell, forItemAtIndexPath indexPath: NSIndexPath) {
    animateCell(cell)
}

func animateCell(cell: UICollectionViewCell) {
    let animation = CABasicAnimation(keyPath: "cornerRadius")
    animation.fromValue = 200
    cell.layer.cornerRadius = 0
    animation.toValue = 0
    animation.duration = 1
    cell.layer.addAnimation(animation, forKey: animation.keyPath)
}

func animateCellAtIndexPath(indexPath: NSIndexPath) {
    guard let cell = collectionView.cellForItemAtIndexPath(indexPath) else { return }
    animateCell(cell)
}

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
    animateCellAtIndexPath(indexPath)
}

这篇关于Swift 2-performBatchUpdates-在UICollectionView框架内可见时，对单元格进行逐一动画处理的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！