ios - 如何在 swift 中动画绘制 UIBezierPath

Question

有人知道如何在自定义 View 中为 UIBezierPath 的绘图设置动画吗？所以看起来 iPhone 拿起了一支笔并在屏幕上绘图，速度足够慢，可以看到它。

就说我有如下路径:

var bezierPath = UIBezierPath()
bezierPath.moveToPoint(CGPointMake(49.5, 14.5))
bezierPath.addCurveToPoint(CGPointMake(106.5, 14.5), controlPoint1: CGPointMake(106.5, 14.5), controlPoint2: CGPointMake(106.5, 14.5))
bezierPath.addCurveToPoint(CGPointMake(119.5, 26.5), controlPoint1: CGPointMake(106.5, 14.5), controlPoint2: CGPointMake(119.5, 14.5))
bezierPath.addCurveToPoint(CGPointMake(119.5, 75.5), controlPoint1: CGPointMake(119.5, 38.5), controlPoint2: CGPointMake(119.5, 75.5))
bezierPath.addCurveToPoint(CGPointMake(106.5, 88.5), controlPoint1: CGPointMake(119.5, 75.5), controlPoint2: CGPointMake(122.5, 88.5))
bezierPath.addCurveToPoint(CGPointMake(49.5, 88.5), controlPoint1: CGPointMake(90.5, 88.5), controlPoint2: CGPointMake(49.5, 88.5))
bezierPath.addCurveToPoint(CGPointMake(36.5, 75.5), controlPoint1: CGPointMake(49.5, 88.5), controlPoint2: CGPointMake(36.5, 89.5))
bezierPath.addCurveToPoint(CGPointMake(36.5, 26.5), controlPoint1: CGPointMake(36.5, 61.5), controlPoint2: CGPointMake(36.5, 26.5))
bezierPath.addCurveToPoint(CGPointMake(49.5, 14.5), controlPoint1: CGPointMake(36.5, 26.5), controlPoint2: CGPointMake(35.5, 14.5))
UIColor.redColor().setFill()
bezierPath.fill()
UIColor.blackColor().setStroke()
bezierPath.lineWidth = 10
bezierPath.stroke()

这会绘制一个圆角矩形，并写在自定义类的 drawRect 函数中。

有谁知道如何为这幅画制作动画吗？

Answer 1

您可以考虑使用 CAShapeLayer并为 strokeEnd 属性设置动画(您可以使用 CABasicAnimation 来控制动画的细节)。 This post有一个例子。