CABasicAnimation动画
//CABasicAnimation-不透明度 @IBAction func cabOpacity() { let animation = CABasicAnimation(keyPath: "opacity") animation!.fromValue = 1.0 animation!.toValue = 0.0 animation.duration = 3.0 self.testImageView.layer.addAnimation(animation, forKey: "Image-opacity") self.testImageView.alpha=0.0; } //开启 clip subview 属性 @IBAction func cabExpend() { //从小到下(如果把Mode 属性改成 Center后,此效果为遮照) let animation = CABasicAnimation(keyPath: "bounds.size") animation!.fromValue = NSValue(CGSize: CGSizeMake(2.0, 2.0)) animation!.toValue = NSValue(CGSize: self.testImageView.frame.size) animation.duration = 3.0 self.testImageView.layer.addAnimation(animation, forKey: "Image-expen") }