Question

我有一个蓝色圆圈的图像，我想让它在椭圆路径中连续循环。我首先创建了一个圆形路径，但它成功了，但是创建一个椭圆形路径会循环圆圈，但会在它再次循环之前暂停。是否有一些我缺少的东西使椭圆形路径循环没有犹豫。这是两个循环的代码。

    func performRotation(){
    let path = UIBezierPath(ovalInRect: CGRectMake(50, 50, 220, 100)) 
    let anim = CAKeyframeAnimation(keyPath: "position")

    anim.path = path.CGPath
    anim.rotationMode = kCAAnimationLinear
    anim.repeatCount = Float.infinity
    anim.duration = 5.0

    //@IBOutlet weak var ball: UIImageView!
    ball.layer.addAnimation(anim, forKey: "animate position along path")

    //this is the circle path that loops without the stutter

    // let ovalStartAngle = CGFloat(90.01 * M_PI/180)
    // let ovalEndAngle = CGFloat(90 * M_PI/180)
    // let ovalRect = CGRectMake(97.5, 58.5, 125, 125)
    //let path = UIBezierPath()
    //path.moveToPoint(CGPoint(x: 200, y: 150))
    //path.addArcWithCenter(CGPointMake(CGRectGetMidX(ovalRect), CGRectGetMidY(ovalRect)),
     //radius: CGRectGetWidth(ovalRect) / 2,
     //startAngle: ovalStartAngle,
     //endAngle: ovalEndAngle, clockwise: true)

     //let anim = CAKeyframeAnimation(keyPath: "position")
     //anim.path = path.CGPath
     //anim.rotationMode = kCAAnimationLinear
     //anim.repeatCount = Float.infinity
     //anim.duration = 5.0
     //ball.layer.addAnimation(anim, forKey: "animate position along path")

    }

Answer 1

尝试设置calculateMode，

，而不是设置rotationMode

anim.calculationMode = kCAAnimationPaced

Swift：在UIBezierPath中使图像连续循环（overInRect）

1 个答案: