swift--动画效果

        for tile in backgrounds{
            
            //现将数字块大小职位原始尺寸的1/10
            tile.layer.setAffineTransform(CGAffineTransform(scaleX: 0.1,y: 0.1))
            
            //设置动画效果，动画时间长度1秒
            UIView.animate(withDuration: 1, delay: 0.01, options: [], animations: { 
                
            }, completion: { (finished) in
               
                UIView.animate(withDuration: 1, animations: { 
                    //完成动画时，数字块复原
                    tile.layer.setAffineTransform(CGAffineTransform.identity)
                })
                
            })
            
        }

        for tile in backgrounds {
            
            tile.alpha = 0
            
            //设置动画效果，动画时间长度1秒
            UIView.animate(withDuration: 1, delay: 0.01, options: [.curveEaseInOut], animations: {
                
            }, completion: { (finished) in
                UIView.animate(withDuration: 1, animations: { 
                    tile.alpha = 1
                })
            })
            
        }

        for tile in backgrounds {
            
            //现将数字快大小之前原始尺寸的1/10
            tile.layer.setAffineTransform(CGAffineTransform(scaleX:0.1,y:0.1))
            
            //设置动画效果，动画时间长度1秒
            UIView.animate(withDuration: 1, delay: 0.01, options: [], animations: { 
                tile.layer.setAffineTransform(CGAffineTransform(scaleX:1,y:1))
            }, completion: { (finished) in
                UIView.animate(withDuration: 0.08, animations: { 
                    tile.layer.setAffineTransform(CGAffineTransform.identity)
                })
            })
            
        }