伪3D效果的实现

func cubeAnimate(targetView: UIView, flightInfo: String) {
// 判断UIView的具体实现类
if targetView.isKindOfClass(UILabel) {
let virtualTargetView = targetView as! UILabel
// 复制UIView，作为底面
let viewCopy = UILabel(frame: virtualTargetView.frame)
viewCopy.alpha = 0
viewCopy.text = flightInfo
viewCopy.font = virtualTargetView.font
viewCopy.textAlignment = virtualTargetView.textAlignment
viewCopy.textColor = virtualTargetView.textColor
viewCopy.backgroundColor = UIColor.clearColor()
// 设置底面UIView的初始位置和高度
viewCopy.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(1.0, 0.1), 

CGAffineTransformMakeTranslation(1.0, viewCopy.frame.height / 2))
self.topView.addSubview(viewCopy)
UIView.animateWithDuration(2, animations: {
// 执行UIView和UIViewCopy的动画
virtualTargetView.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(1.0, 0.1), 

CGAffineTransformMakeTranslation(1.0, -virtualTargetView.frame.height / 2))
virtualTargetView.alpha = 0
viewCopy.alpha = 1
viewCopy.transform = CGAffineTransformIdentity
}, completion: { _ in
// 当动画执行完毕后，将UIViewCopy的信息赋值给UIView，并还原UIView的状态，即与UIViewCopy相同的状态，然后移除UIViewCopy
virtualTargetView.alpha = 1
virtualTargetView.text = viewCopy.text
virtualTargetView.transform = CGAffineTransformIdentity
viewCopy.removeFromSuperview()
})
} else if targetView.isKindOfClass(UIImageView) {
let virtualTargetView = targetView as! UIImageView
let viewCopy = UIImageView(frame: virtualTargetView.frame)
viewCopy.alpha = 0
viewCopy.image = UIImage(named: flightInfo)
viewCopy.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(1.0, 0.1), 

CGAffineTransformMakeTranslation(1.0, viewCopy.frame.height / 2))
self.topView.addSubview(viewCopy)
UIView.animateWithDuration(2, animations: {
virtualTargetView.transform = CGAffineTransformConcat(CGAffineTransformMakeScale(1.0, 0.1), 

CGAffineTransformMakeTranslation(1.0, -virtualTargetView.frame.height / 2))
virtualTargetView.alpha = 0
viewCopy.alpha = 1
viewCopy.transform = CGAffineTransformIdentity
}, completion: { _ in
virtualTargetView.alpha = 1
virtualTargetView.image = viewCopy.image
virtualTargetView.transform = CGAffineTransformIdentity
viewCopy.removeFromSuperview()
})
}
}