我想将动画添加到集合视图中，列表非常缓慢地上下移动，在集合视图重新加载数据后我启动计时器并添加重复动画的方法，有我的代码，动画行为非常在动画期间，我丢失了列表数据。 有我的代码怎么解决这个？ 谢谢你的回复。
fileprivate func startTimer() {
if timer == nil {
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: (#selector(addAnimationToCollection)), userInfo: nil, repeats: true)
}
}
func scrollToIndexPath(path: NSIndexPath) {
let atts = self.collectionView!.layoutAttributesForItem(at: path as IndexPath)
self.endPoint = CGPoint(x: 0, y: atts!.frame.origin.y - self.collectionView.contentInset.top)
self.scrollPoint = self.collectionView!.contentOffset
self.scrollingUp = self.collectionView!.contentOffset.y > self.endPoint!.y
self.scrollTimer?.invalidate()
self.scrollTimer = Timer.scheduledTimer(timeInterval:0.01, target: self, selector: (#selector(scrollTimerTriggered(timer:))), userInfo: nil, repeats: true)
}
func scrollTimerTriggered(timer: Timer) {
let dif = fabs(self.scrollPoint!.y - self.endPoint!.y) / 10000.0
let modifier: CGFloat = self.scrollingUp ? -2 : 2
self.scrollPoint = CGPoint(x: self.scrollPoint!.x, y: self.scrollPoint!.y + (modifier * dif))
self.collectionView?.contentOffset = self.scrollPoint!
let maximumOffset = self.collectionView.contentSize.height - self.collectionView.frame.size.height
if self.scrollingUp && self.collectionView!.contentOffset.y < maximumOffset {
self.collectionView!.contentOffset = self.endPoint!
timer.invalidate()
} else if !self.scrollingUp && self.collectionView!.contentOffset.y >= self.endPoint!.y {
self.collectionView!.contentOffset = self.endPoint!
timer.invalidate()
}
}
fileprivate func invelidTimer() {
if timer != nil {
timer?.invalidate()
timer = nil
}
if scrollTimer != nil {
scrollTimer?.invalidate()
scrollTimer = nil
}
}
@objc func addAnimationToCollection() {
let currentOffset = self.collectionView.contentOffset.y
let maximumOffset = self.collectionView.contentSize.height - self.collectionView.frame.size.height
if maximumOffset - currentOffset < 0 {
let first : NSIndexPath = NSIndexPath(row: 0, section: 0)
self.scrollToIndexPath(path: first)
}
else {
let last : NSIndexPath = NSIndexPath(row: self.collectionList.count - 1, section: 0)
self.scrollToIndexPath(path: last)
}
}