所以我有一个 UIView 附加了一个 PanGestureRecognizer 允许我上下移动 View 。当我向上移动 View 时，我想降低按钮的 alpha，而当我向下移动 View 时，我想将其恢复正常。
我曾尝试在按钮卡入某个位置时单独为按钮设置动画，但这会破坏我的 PropertyAnimator。
我当前的实现可以找到，前提是我的手指在 View 上，因为这会从识别器返回 .changed 状态。但我也有实现，当 View 在沿 y 轴 的某个点释放时，将 View 对齐到位。问题是它没有达到 .changed 状态，因此改变了我的 hideAnimator.fractionComplete，使按钮在其动画中途离开。
初始化属性动画方法
func initPropertyAnimator() {
hideAnimator = UIViewPropertyAnimator(duration: 0.18, curve: .easeInOut, animations: {
self.requestButton.alpha = 0
})
}
识别器状态 panGesture(recognizer: UIPanGestureRecognizer)
let currentY = self.frame.minY
switch recognizer.state {
case .began:
print("Began")
case .changed:
// Property animator
let offset: CGFloat = window!.frame.height-194
let percentage: CGFloat = (offset-currentY)/100
print(percentage)
hideAnimator?.fractionComplete = CGFloat(percentage)
case .ended:
// Snap back below 80 (y)
if currentY < 80 || currentY > 80 && currentY < halfWayPoint
{
self.animator?.stopAnimation(true)
UIView.animate(withDuration:0.62, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations:
{
recognizer.view!.frame = CGRect(x: 0, y: 80, width: self.frame.width, height: self.frame.height)
self.requestButton.alpha = 0
self.houseView.frame = CGRect(x: 16, y: 87, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339, width: self.boxWidth, height: 68)
}, completion: { (true) in
})
}
// Snap back above partial (y)
if currentY > partialY || currentY < partialY && currentY > halfWayPoint
{
self.animator?.stopAnimation(true)
UIView.animate(withDuration:0.62, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations:
{
recognizer.view!.frame = CGRect(x: 0, y: partialY, width: self.frame.width, height: self.frame.height)
self.requestButton.alpha = 1
self.houseView.frame = CGRect(x: 16, y: 87+200, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171+200, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255+200, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339+200, width: self.boxWidth, height: 68)
}, completion: { (true) in
})
}
最佳答案
我通过添加一个 bool 值 来检查 View 当前是否已展开来解决这个问题，然后根据true 或false 加载相应的动画。我知道这不是最好的做事方式，因为您无需编写太多代码就可以将动画返回到其原始位置。无论如何，它有效，所以我会顺其自然。
顺便说一句，我非常欢迎任何可以帮助改进此代码的人，它确实需要一些 TLC。
这是处理我的 panGestureRecogniser
// MARK: - Pan gesture
@objc func panGesture(recognizer: UIPanGestureRecognizer) {
let window = UIApplication.shared.keyWindow
let translation = recognizer.translation(in: self)
let currentY = self.frame.minY
let partialY = (window?.frame.height)!-194
let halfWayPoint = ((window?.frame.height)!/2)-40
self.frame = CGRect(x: 0, y: currentY + translation.y, width: self.frame.width, height: self.frame.height)
recognizer.setTranslation(CGPoint.zero, in: self)
switch recognizer.state {
case .began:
print("Began")
if isExpanded
{
animator = UIViewPropertyAnimator(duration: 0.18, curve: .easeInOut, animations: {
self.requestButton.alpha = 1
self.houseView.alpha = 0
self.officeView.alpha = 0
self.gardenView.alpha = 0
self.carView.alpha = 0
self.houseView.frame = CGRect(x: 16, y: 87+200, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171+200, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255+200, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339+200, width: self.boxWidth, height: 68)
})
self.animator?.isReversed = true
}
else
{
animator = UIViewPropertyAnimator(duration: 0.18, curve: .easeInOut, animations: {
self.requestButton.alpha = 0
self.houseView.alpha = 1
self.officeView.alpha = 1
self.gardenView.alpha = 1
self.carView.alpha = 1
self.houseView.frame = CGRect(x: 16, y: 87, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339, width: self.boxWidth, height: 68)
})
self.animator?.isReversed = false
}
animator?.startAnimation()
animator?.pauseAnimation()
case .changed:
// Property animator
let offset: CGFloat = window!.frame.height-194
let fraction: CGFloat = (offset-currentY)/4
let percentage = fraction/100
print(percentage)
animator?.fractionComplete = CGFloat(percentage)
// Prevent scrolling up past y:0
if currentY <= 0
{
self.frame = CGRect(x: 0, y: 0, width: self.frame.width, height: self.frame.height)
}
case .ended:
// Snap to 80 (y) (expanded)
if currentY < 80 || currentY > 80 && currentY < halfWayPoint
{
self.animator?.stopAnimation(true)
UIView.animate(withDuration:0.62, delay: 0.0, usingSpringWithDamping: 0.62, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations:
{
recognizer.view!.frame = CGRect(x: 0, y: 80, width: self.frame.width, height: self.frame.height)
self.requestButton.alpha = 0
self.houseView.alpha = 1
self.officeView.alpha = 1
self.gardenView.alpha = 1
self.carView.alpha = 1
self.houseView.frame = CGRect(x: 16, y: 87, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339, width: self.boxWidth, height: 68)
}, completion: { (true) in
self.isExpanded = true
})
}
// Snap back to partial (y) (original position)
if currentY > partialY || currentY < partialY && currentY > halfWayPoint
{
self.animator?.stopAnimation(true)
UIView.animate(withDuration:0.62, delay: 0.0, usingSpringWithDamping: 0.62, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations:
{
recognizer.view!.frame = CGRect(x: 0, y: partialY, width: self.frame.width, height: self.frame.height)
self.requestButton.alpha = 1
self.houseView.alpha = 0
self.officeView.alpha = 0
self.gardenView.alpha = 0
self.carView.alpha = 0
self.houseView.frame = CGRect(x: 16, y: 87+200, width: self.boxWidth, height: 68)
self.officeView.frame = CGRect(x: 16, y: 171+200, width: self.boxWidth, height: 68)
self.carView.frame = CGRect(x: 16, y: 255+200, width: self.boxWidth, height: 68)
self.gardenView.frame = CGRect(x: 16, y: 339+200, width: self.boxWidth, height: 68)
}, completion: {(true) in
self.isExpanded = false
})
}
case .cancelled:
print("Cancelled")
case .failed:
print("Failed")
default:
print("Default")
}
}
关于ios - Swift 如何使用带有平移手势的属性动画器，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/50090381/