override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. let rect = CGRect(x: 0, y: 0, 499, height: 726) let imageView = UIImageView(frame: rect) let image = UIImage(named: "Pic3") imageView.image = image//给图像视图添加要显示的图片 self.view.addSubview(imageView) let animation = CATransition()//初始化一个过度动画实例 animation.duration = 2//设置动画时长2秒 //设置动画的播放速度为由慢至块 animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut) animation.type = kCATransitionPush//设置动画的类型为入场动画(图片从左往右飘进来) imageView.layer.add(animation, forKey: "Push")//将动画指定给图像视图的层 }