是否可以使用新的iOS 10 UIViewPropertyAnimator为圆形路径中的视图设置动画?
我知道可以按照How do I animate a UIView along a circular path?
使用CAKeyframeAnimation完成如何使用新API获得相同的结果?
答案 0 :(得分:1)
我最终得到了以下内容。基本上,计算圆上的点并使用animateKeyFrames在它们之间移动。
let radius = CGFloat(100.0)
let center = CGPoint(x: 150.0, y: 150.0)
let animationDuration: TimeInterval = 3.0
let animator = UIViewPropertyAnimator(duration: animationDuration, curve: .linear)
animator.addAnimations {
UIView.animateKeyframes(withDuration: animationDuration, delay: 0, options: [.calculationModeLinear], animations: {
let points = 1000
let slice = 2 * CGFloat.pi / CGFloat(points)
for i in 0..<points {
let angle = slice * CGFloat(i)
let x = center.x + radius * CGFloat(sin(angle))
let y = center.y + radius * CGFloat(cos(angle))
let duration = 1.0/Double(points)
let startTime = duration * Double(i)
UIView.addKeyframe(withRelativeStartTime: startTime, relativeDuration: duration) {
ninja.center = CGPoint(x: x, y: y)
}
}
})
}
animator.startAnimation()