swift - UIButton 心跳动画

Question

我为 UIButton 创建了心跳动画。但是，没有办法停止这个动画，因为它是一个无限循环的代码。在修改了许多 UIView 动画代码块之后，我一直无法获得 UIViewAnimationOptions.Repeat 来生成我需要的内容。如果我能做到这一点，我可以简单地 button.layer.removeAllAnimations() 来删除动画。允许删除动画的编写方法是什么？我在想可能是一个计时器，但如果要同时播放多个动画，那可能会有点困惑。

func heartBeatAnimation(button: UIButton) {

    button.userInteractionEnabled = true
    button.enabled = true

    func animation1() {

        UIView.animateWithDuration(0.5, delay: 0.0, options: [], animations: { () -> Void in

            button.transform = CGAffineTransformMakeScale(2.0, 2.0)
            button.transform = CGAffineTransformIdentity

        }, completion: nil)

        UIView.animateWithDuration(0.5, delay: 0.5, options: [], animations: { () -> Void in

            button.transform = CGAffineTransformMakeScale(2.0, 2.0)
            button.transform = CGAffineTransformIdentity

            }) { (Bool) -> Void in

                delay(2.0, closure: { () -> () in

                    animation2()

                })       
        }
    }

    func animation2() {

        UIView.animateWithDuration(0.5, delay: 0.0, options: [], animations: { () -> Void in

            button.transform = CGAffineTransformMakeScale(2.0, 2.0)
            button.transform = CGAffineTransformIdentity

            }, completion: nil)

        UIView.animateWithDuration(0.5, delay: 0.5, options: [], animations: { () -> Void in

            button.transform = CGAffineTransformMakeScale(2.0, 2.0)
            button.transform = CGAffineTransformIdentity

            }) { (Bool) -> Void in

                delay(2.0, closure: { () -> () in

                    animation1()

                })
        }
    }

    animation1()

}

Answer 1

这非常有效。阻尼和 Spring 需要稍微调整一下，但这可以解决问题。 removeAllAnimations() 清除动画并将按钮返回到正常状态。

button.userInteractionEnabled = true
button.enabled = true

let pulse1 = CASpringAnimation(keyPath: "transform.scale")
pulse1.duration = 0.6
pulse1.fromValue = 1.0
pulse1.toValue = 1.12
pulse1.autoreverses = true
pulse1.repeatCount = 1
pulse1.initialVelocity = 0.5
pulse1.damping = 0.8

let animationGroup = CAAnimationGroup()
animationGroup.duration = 2.7
animationGroup.repeatCount = 1000
animationGroup.animations = [pulse1]

button.layer.addAnimation(animationGroup, forKey: "pulse")

这篇文章很有帮助:CAKeyframeAnimation delay before repeating