我有一个关键帧动画显示一个快速的卡交易效果。我使用第二个动画（使用.beginfraomcurrentstate…）取消交易，如果你按下按钮。这对简单的单视图动画有效。但是在这里，按下按钮后会有2-10秒的延迟，大概是在运行每个取消动画时。有没有一种更简单、更顺畅的方法来实现我想要的目标（立即取消交易）。
下面是设置交易动画的代码片段：
let durationSlice = 1.0/Double(numCards*numPlayers+1)
var durationSliceStart : Double = 0
UIView.animateKeyframesWithDuration(FiveKings.ANIMATION_250MS*(Double(numCards)*Double(numPlayers)+1), delay: 0.0 ,
options: [.CalculationModeCubic],
animations: {
for iCard in 0..<numCards {
durationSliceStart = Double(iCard*numPlayers) * durationSlice
//translate the cards off the pile and to each mini Hand (and they stay visible)
for iPlayer in 0..<numPlayers {
//Animate the card into view at the start of this set
UIView.addKeyframeWithRelativeStartTime(durationSliceStart+Double(iPlayer)*durationSlice, relativeDuration: 0.0, animations: {
pileCardViews[iCard*numPlayers + iPlayer].alpha = 1.0
})
//add a random amount of translation and rotation to simulate messy cards
let messyX = CGFloat((drand48()-0.5) * MESSY_CARD_XY_OFFSET) * self.mDrawPile.bounds.width
let messyY = CGFloat((drand48()-0.5) * MESSY_CARD_XY_OFFSET) * self.mDrawPile.bounds.height
let messyRotation = CGFloat((drand48()-0.5) * MESSY_CARD_ANGLE) * 2.0 * 3.14
//convert the destination miniHand into the coordinates of mDrawPile
let miniHandLayout = self.mGame.players.getPlayer(iPlayer).miniHandLayout!
miniHandDestinationPoint = miniHandLayout.cardView.convertPoint(CGPoint(x: 0,y: 0), toView: self.mDrawPile)
UIView.addKeyframeWithRelativeStartTime(durationSliceStart+Double(iPlayer)*durationSlice, relativeDuration: durationSlice, animations: {
pileCardViews[iCard*numPlayers + iPlayer].transform = CGAffineTransformConcat(
CGAffineTransformMakeRotation(3.14+messyRotation),
CGAffineTransformMakeTranslation(miniHandDestinationPoint.x + messyX, miniHandDestinationPoint.y + messyY))
if iCard == 0 {miniHandLayout.cardView.alpha = 1.0}
})
}
}//end iCard
//animate a card to the DiscardPile
let discardPileDestination = self.mDiscardPile.convertPoint(CGPoint(x: 0, y: 0), toView: self.mDrawPile)
UIView.addKeyframeWithRelativeStartTime(durationSliceStart+Double(numPlayers)*durationSlice, relativeDuration: durationSlice, animations:
{
pileCardViews[numCards*numPlayers].transform = CGAffineTransformMakeTranslation(discardPileDestination.x, discardPileDestination.y)
pileCardViews[numCards*numPlayers].alpha = 1.0
})
},
//completion block removes the added cards
completion: {(_ : Bool) in
//remove the added cards
for pcv in pileCardViews {pcv.removeFromSuperview()}
self.afterDealing()
}
)//end UIView.animateKeyFramesWithDuration
以下是按“跳过交易”按钮时运行的代码：
if !mDealingPileCards.isEmpty {
for pcv in self.mDealingPileCards {pcv.stopAnimation()} //also seems to call completion handler
self.mDealingPileCards.removeAll(keepCapacity: true)
self.setShowHint(stringKey: "toDisableDealing", setShowHint: FiveKings.HandleHint.SET_AND_SHOW_HINT, hintLevel: GameDifficulty.MEDIUM)
}
stopAnimation的实现是对UIView的扩展：func stopAnimation() {
UIView.animateWithDuration(0.0, delay: 0.0, options: [.BeginFromCurrentState],
animations: {
self.alpha = 1.0
self.transform = CGAffineTransformIdentity
}, completion: nil)
}
编辑：我尝试过使用
...layer.removeAllAnimations，但同样的延迟问题也会发生，也许是在运行完成处理程序时？ 最佳答案
要取消动画，只需对正在设置动画的每个层（或每个视图的层）说removeAllAnimations。您还需要决定现在希望该视图出现在什么地方，但这是一个不同的问题（换句话说，您必须考虑取消实际上包括什么）。