Question

在另一个问题中，如何回答动画： Draw line animated

然后我尝试同时添加一个动画视图。我想创建两个动画路径，它们在同一CGPoint会面，但有不同的路径到达那里。我希望两个路径同时启动并同时结束动画。我目前的方法是创建第二个UIBezierPath名为path2，以及第二个CAShapeLayer名为shapeLayer2，但第二个路径只是覆盖第一个路径。我非常确定两条路径都需要不同的CAShapeLayer，因为每条路径都有不同的属性。我似乎需要将CAShapeLayer实例添加为view.layer子图层，但它似乎无法正常工作。为了达到预期的效果，我应该做些什么？

Answer 1

这是最终奏效的。

    func animatePath() {

    // create whatever path you want
    let path = UIBezierPath()
    path.move(to: CGPoint(x: 10, y: 100))
    path.addLine(to: CGPoint(x: 200, y: 50))
    path.addLine(to: CGPoint(x: 200, y: 240))

    // create whatever path you want
    let path2 = UIBezierPath()
    let bottomStartX = view.frame.maxX - 10
    let bottomStartY = view.frame.maxY - 100
    path2.move(to: CGPoint(x: bottomStartX, y: bottomStartY))
    path2.addLine(to: CGPoint(x: bottomStartX - 100, y: bottomStartY - 100))
    path2.addLine(to: CGPoint(x: 200, y: 240))

    // create shape layer for that path
    let shapeLayer = CAShapeLayer()
    shapeLayer.fillColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 0).cgColor
    shapeLayer.strokeColor = #colorLiteral(red: 1, green: 0, blue: 0, alpha: 1).cgColor
    shapeLayer.lineWidth = 4
    shapeLayer.path = path.cgPath

    let shapeLayer2 = CAShapeLayer()
    shapeLayer2.fillColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 0).cgColor
    shapeLayer2.strokeColor = UIColor.blue.cgColor
    shapeLayer2.lineWidth = 4
    shapeLayer2.path = path.cgPath

    // animate it
    view.layer.addSublayer(shapeLayer)
    view.layer.addSublayer(shapeLayer2)
    let animation = CABasicAnimation(keyPath: "strokeEnd")
    animation.fromValue = 0
    animation.duration = 2
    shapeLayer.add(animation, forKey: "MyAnimation")


    let animation2 = CABasicAnimation(keyPath: "strokeEnd")
    animation2.fromValue = 0
    animation2.duration = 2
    shapeLayer2.add(animation2, forKey: "MyAnimation")

    // save shape layer
    self.shapeLayer = shapeLayer
}

如何以编程方式在swift中同时动画两个视图？

1 个答案: