Ios 当UIPercentDrivenInteractiveTransition结束一半时触发取消动画
如果交互结束且动画被取消,强制视图控制器的自定义转换回到原始位置是否是一种良好的做法。我有下面的实现,它决定何时关闭“平移”手势上的视图控制器。如果平移手势提前结束,我希望在考虑持续时间与平移手势的<代码>进度代码>值成比例之前,将动画设置回原始位置,就像它的显示方式一样Ios 当UIPercentDrivenInteractiveTransition结束一半时触发取消动画,ios,uiviewanimationtransition,Ios,Uiviewanimationtransition,如果交互结束且动画被取消,强制视图控制器的自定义转换回到原始位置是否是一种良好的做法。我有下面的实现,它决定何时关闭“平移”手势上的视图控制器。如果平移手势提前结束,我希望在考虑持续时间与平移手势的进度值成比例之前,将动画设置回原始位置,就像它的显示方式一样 protocol AnimationControllerDelegate: AnyObject { func shouldHandlePanelInteractionGesture() -> Bool } typealias P
protocol AnimationControllerDelegate: AnyObject {
func shouldHandlePanelInteractionGesture() -> Bool
}
typealias PanGestureHandler = AnimationControllerDelegate & UIViewController & Animatable
final class CustomInteractionController: UIPercentDrivenInteractiveTransition, UIGestureRecognizerDelegate {
var interactionInProgress: Bool = false
private var shouldCompleteTransition: Bool = false
private var startTransitionY: CGFloat = 0
private var panGestureRecognizer: UIPanGestureRecognizer?
private weak var viewController: PanGestureHandler?
func wireToViewController(viewController: Any) {
guard let viewControllerDelegate = viewController as? PanGestureHandler else {
return
}
self.viewController = viewControllerDelegate
let panGesture = UIPanGestureRecognizer(target: self, action: #selector(handlePanGestureRecognizer(_:)))
panGestureRecognizer = panGesture
panGestureRecognizer?.delegate = self
self.viewController?.view.addGestureRecognizer(panGesture)
}
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer,
shouldRecognizeSimultaneouslyWith
otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return true
}
@objc
func handlePanGestureRecognizer(_ gestureRecognizer: UIPanGestureRecognizer) {
guard let childView = gestureRecognizer.view,
let parentView = childView.superview,
let panGestureHandler = viewController else {
return
}
switch gestureRecognizer.state {
case .began:
break
case .changed:
let translation = gestureRecognizer.translation(in: parentView)
let velocity = gestureRecognizer.velocity(in: parentView)
let state = gestureRecognizer.state
if !panGestureHandler.shouldHandlePanelInteractionGesture() && percentComplete == 0 {
return
}
let verticalMovement = translation.y / childView.bounds.height
let downwardMovement = fmaxf(Float(verticalMovement), 0.0)
let downwardMovementPercent = fminf(downwardMovement, 1.0)
let progress = CGFloat(downwardMovementPercent)
let alphaValue = (1 - progress) * 0.4
panGestureHandler.shadowView.backgroundColor = Safety.Colors.backgroundViewColor(for: alphaValue)
if abs(velocity.x) > abs(velocity.y) && state == .began {
return
}
if !interactionInProgress {
interactionInProgress = true
startTransitionY = translation.y
viewController?.dismiss(animated: true, completion: nil)
} else {
shouldCompleteTransition = progress > 0.3
update(progress)
}
case .cancelled:
interactionInProgress = false
startTransitionY = 0
cancel()
case .ended:
interactionInProgress = false
startTransitionY = 0
if !shouldCompleteTransition {
// Can I call a custom transition here back to original position?
cancel()
} else {
finish()
}
case .failed:
interactionInProgress = false
startTransitionY = 0
cancel()
default:
break
}
}
}
如果交互结束且动画被取消,强制视图控制器的自定义转换回到原始位置是否是一种良好的做法
是的,我认为如果用户取消手势,最好将其反转。但你不必“强迫”它。完成转换,只需指示是要完成还是要反转。因此,如果取消动画,它将自动反转并返回到自动为您设置的位置。您无需执行任何操作,只需取消
当然,这假定在animator中的动画完成块中,您在completeTransition
中指示动画是否完成:
UIView.animate(withDuration: 0.25, animations: {
...
}, completion: { _ in
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
因此,如果没有取消,动画将完成。但如果它被取消,它将逆转
就个人而言,在手势识别器中,我通常会执行以下操作:
- 如果手势
为状态
,我将:开始
- 实例化
UIViewControllerTransitionDelegate将从
返回的interactionControllerForPresentation(使用)
;及UIPercentDrivenInteractiveTransition
- 执行
/显示
解除
UIPercentDrivenInteractiveTransition
- 实例化
- 当手势更新为
的.changed
状态时,只需
更新
;及UIPercentDrivenInteractiveTransition
- 完成后,您可以
或完成
它。而取消
将自动触发反向动画cancel
@objc func handleLeftToRightPan(_ gesture: UIPanGestureRecognizer) {
let percent = (gesture.translation(in: gesture.view).x) / gesture.view!.bounds.width
switch gesture.state {
case .began:
interactionController = UIPercentDrivenInteractiveTransition()
dismiss(animated: true)
interactionController?.update(percent)
case .changed:
interactionController?.update(percent)
case .ended, .cancelled:
let velocity = gesture.velocity(in: gesture.view).x
if velocity > 0 || (velocity == 0 && percent > 0.5) {
interactionController?.finish()
} else {
interactionController?.cancel()
}
interactionController = nil
default:
break
}
}
就个人而言,对于finish
与cancel
逻辑,我检查是否:
是否在手势的方向上(从左到右的“驳回”手势,这意味着我检查它是否为正速度
速度)。。。这意味着,如果用户点击,即使是屏幕的一小部分,我仍然会认为完全过渡的意图;x
- 只有当
为零时,我才检查完成百分比(例如,如果他们走了¾个方向,停下来,然后放开,我假设他们想速度
手势,但如果他们只走了¼个方向,停下来,然后放开,我假设他们打算取消手势完成
不用说,如果他们扭转了他们的手势的方向,我认为他们完全转变的意图被取消了 。
cancel
,动画会自动反转。因此,在这里,我开始从第二个视图控制器返回到第一个视图控制器,但是cancel
UIPercentDrivenInteractiveTransition(在这种情况下,通过反转手势的方向并放开),我的动画制作者将在其完成处理程序中,将适当的Bool
值传递给其完成处理程序中的completeTransition
,并在我不做任何工作的情况下自动设置动画: