按钮在动画期间不响应点击

Question

我为按钮绘制了一个圆形路径（scienceCircle） -

var sciencePath = UIBezierPath()
    sciencePath.moveToPoint(CGPoint(x: 228, y: 132))
    sciencePath.addCurveToPoint(CGPoint(x: 228, y: 132), controlPoint1: CGPoint(x: 208, y: 153), controlPoint2: CGPoint(x: 248, y: 114))
    let anim2 = CAKeyframeAnimation(keyPath: "position")
    anim2.path = sciencePath.CGPath
    anim2.repeatCount = Float.infinity
    anim2.duration = 7.0

scienceCircle.layer.addAnimation(anim2, forKey: "animate position along path")

这是我输入的用于添加按钮的代码 -

var scienceCircle = InterestSubCircles() //A Cocoa Touch Class with a drawRect method to make the button a circle.
scienceCircle.frame = CGRect(x: 183, y: 137, width: 100, height: 100)
self.view.addSubview(scienceCircle)

此按钮继续以圆圈移动。现在，我不能在按钮移动时按下按钮（当它移动时）。我只能在它处于原始位置时点击它。基本上，我不能通过动画连续移动按钮。我能在这做什么？请帮忙。