如何在动画播放时更改为CABasicAnimation的toValue/fromValue

// 导入需要的框架
import UIKit

// 创建一个视图
let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
view.backgroundColor = UIColor.red

// 创建一个CABasicAnimation对象
let animation = CABasicAnimation(keyPath: "position.x")

// 设置动画的起始值和结束值
animation.fromValue = view.layer.position.x
animation.toValue = view.layer.position.x + 100

// 设置动画的其他属性
animation.duration = 1.0
animation.repeatCount = Float.infinity

// 将动画添加到视图的图层上
view.layer.add(animation, forKey: "positionAnimation")

// 在动画播放过程中更改toValue/fromValue
DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
    // 获取当前动画的图层动画
    if let currentAnimation = view.layer.animation(forKey: "positionAnimation") as? CABasicAnimation {
        // 更改toValue/fromValue
        currentAnimation.toValue = view.layer.position.x - 100
        currentAnimation.fromValue = view.layer.position.x
    }
}