Swift 套现层复制品_Swift_Cashapelayer_Cabasicanimation

Swift 套现层复制品

swift

Swift 套现层复制品,swift,cashapelayer,cabasicanimation,Swift,Cashapelayer,Cabasicanimation,我试图在给定的x和y坐标下每隔20毫秒添加一次CAShapelayer。我想形状消失了一秒钟（像一个跟踪器）。我创建的功能可以正常工作，形状在正确的位置创建并逐渐消失。但我得到了多余的形状留下混乱的屏幕上 func shadowBall (x: CGFloat, y: CGFloat){ let xpos : CGFloat = ((self.frame.width/2) + x) let ypos : CGFloat = ((self.frame.height/2) + y)

我试图在给定的x和y坐标下每隔20毫秒添加一次CAShapelayer。我想形状消失了一秒钟（像一个跟踪器）。我创建的功能可以正常工作，形状在正确的位置创建并逐渐消失。但我得到了多余的形状留下混乱的屏幕上

func shadowBall (x: CGFloat, y: CGFloat){

    let xpos : CGFloat = ((self.frame.width/2) + x)
    let ypos : CGFloat = ((self.frame.height/2) + y)

    let shadowBall = CAShapeLayer()
    let shadowBalllRadius :CGFloat = 4
    let shadowBallPath : UIBezierPath = UIBezierPath(ovalInRect: CGRect(x: xpos, y: ypos, width: CGFloat(shadowBalllRadius*2), height: CGFloat(shadowBalllRadius*2)))

    shadowBall.path = shadowBallPath.CGPath
    shadowBall.fillColor = UIColor.clearColor().CGColor
    shadowBall.strokeColor = UIColor.whiteColor().CGColor
    shadowBall.lineWidth = 0.5

    let animation: CABasicAnimation = CABasicAnimation(keyPath: "strokeColor")
    animation.fromValue = UIColor.whiteColor().CGColor
    animation.toValue = UIColor.clearColor().CGColor
    animation.duration = 1.0;
    animation.repeatCount = 0;
    animation.removedOnCompletion = true
    animation.additive = false

    self.layer.addSublayer(shadowBall)
    shadowBall.addAnimation(animation, forKey: "strokeColor")

}

问题是，当动画完成时，它会将

strokeColor

恢复为原始颜色。您应该将原始形状层的

strokeColor

设置为

clearColor（）

，这样，当您完成从

whiteColor（）

到

clearColor（）

的动画制作时，它将保持在

clearColor（）

您还可以将层的

fillMode

设置为

kCAFillModeForwards

，并将

removedOnCompletion

设置为

false

，这样层将保持其“动画结束”状态。但我个人只会按照上面所述设置

strokeColor

，因为使用

true

的

removedOnCompletion

会干扰

animationDidStop

（见下文）

此外，我可能建议您在动画完成后删除该层，这样它就不会继续消耗内存，尽管它不再可见

func shadowBall (x: CGFloat, y: CGFloat) {
    let xpos: CGFloat = ((self.frame.width/2) + x)
    let ypos: CGFloat = ((self.frame.height/2) + y)

    let shadowBall = CAShapeLayer()
    let shadowBalllRadius: CGFloat = 4
    let shadowBallPath = UIBezierPath(ovalInRect: CGRect(x: xpos, y: ypos, width: CGFloat(shadowBalllRadius*2), height: CGFloat(shadowBalllRadius*2)))

    shadowBall.path = shadowBallPath.CGPath
    shadowBall.fillColor = UIColor.clearColor().CGColor
    shadowBall.strokeColor = UIColor.clearColor().CGColor
    shadowBall.lineWidth = 0.1

    let animation = CABasicAnimation(keyPath: "strokeColor")
    animation.fromValue = UIColor.whiteColor().CGColor
    animation.toValue = UIColor.clearColor().CGColor
    animation.duration = 1.0
    animation.repeatCount = 0
    animation.removedOnCompletion = true
    animation.additive = false

    animation.delegate = self
    animation.setValue(shadowBall, forKey: "animationLayer")

    self.layer.addSublayer(shadowBall)
    shadowBall.addAnimation(animation, forKey: "strokeColor")
}

override func animationDidStop(anim: CAAnimation, finished flag: Bool) {
    if let layer = anim.valueForKey("animationLayer") as? CALayer {
        layer.removeFromSuperlayer()
    }
}

请参见

问题在于，当动画完成时，它会将

strokeColor