在Swift中设置双精度变量的动画

import QuartzCore

let layer = CALayer()

layer.position = CGPoint(x: 100, y: 100)
layer.bounds = CGRect(x: 0, y: 0, width: 100, height: 100)
layer.backgroundColor = UIColor.red.cgColor

let animation = CABasicAnimation(keyPath: "position")
animation.fromValue = NSValue(cgPoint: CGPoint(x: 100, y: 100))
animation.toValue = NSValue(cgPoint: CGPoint(x: 200, y: 200))
animation.duration = 1.0

layer.add(animation, forKey: "positionAnimation")

view.layer.addSublayer(layer)