Xcode9學習筆記54 - 使用CATransaction Reveal製作動畫

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        let rect = CGRect(x: 0, y: 0, width: 499, height: 726)
        let imageView = UIImageView(frame: rect)
        
        let image = UIImage(named: "Pic3")
        imageView.image = image//給圖像視圖添加要顯示的圖片
        
        self.view.addSubview(imageView)
        
        let animation = CATransition()
        animation.duration = 2//設置動畫時長2秒
        //設置動畫的播放速度爲由慢至塊
        animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseOut)
        animation.type = kCATransitionReveal//設置動畫的類型爲漸顯動畫
        
        imageView.layer.add(animation, forKey: "Reveal")//將動畫指定給圖像視圖的層
    }