我对 UINavigationController 进行了子类化，并创建了一个非交互式动画对象来处理推送和弹出转换。要完成此操作，我如何添加 UIScreenEdgePanGestureRecognizer 来处理下面的自定义弹出动画？我对从这里去哪里感到困惑，所以任何帮助都会很棒，谢谢!
class CustomNavigationController: UINavigationController {
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
isNavigationBarHidden = true
}
}
extension CustomNavigationController: UINavigationControllerDelegate {
// noninteractive animator objects
func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
switch operation {
case .push:
return CustomPushAnimator()
case .pop:
return CustomPopAnimator()
default:
return nil
}
}
// the interactive animator controller
func navigationController(_ navigationController: UINavigationController, interactionControllerFor animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
switch animationController {
case is CustomPopAnimator:
return CustomInteractiveController()
default:
return nil
}
}
// the noninteractive push animator
class CustomPushAnimator: NSObject, UIViewControllerAnimatedTransitioning {
// push transition duration
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.2
}
// push transition animation
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let viewWidth = UIScreen.main.bounds.width
let viewHeight = UIScreen.main.bounds.height
let containerView = transitionContext.containerView
let toViewController = transitionContext.viewController(forKey: .to)
containerView.addSubview((toViewController?.view)!)
toViewController?.view.frame = CGRect(x: viewWidth, y: 0, width: viewWidth, height: viewHeight)
UIView.animate(withDuration: transitionDuration(using: transitionContext), delay: 0, options: UIViewAnimationOptions.curveEaseInOut, animations: {
toViewController?.view.frame = CGRect(x: 0, y: 0, width: viewWidth, height: viewHeight)
}, completion: { finished in
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
}
}
// the noninteractive pop animator
class CustomPopAnimator: NSObject, UIViewControllerAnimatedTransitioning {
// pop transition duration
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.2
}
// pop transition animation
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let viewWidth = UIScreen.main.bounds.width
let viewHeight = UIScreen.main.bounds.height
let containerView = transitionContext.containerView
let fromViewController = transitionContext.viewController(forKey: .from)
let toViewController = transitionContext.viewController(forKey: .to)
containerView.insertSubview((toViewController?.view)!, belowSubview: (fromViewController?.view)!)
UIView.animate(withDuration: transitionDuration(using: transitionContext), delay: 0, options: UIViewAnimationOptions.curveEaseInOut, animations: {
fromViewController?.view.frame = CGRect(x: viewWidth, y: 0, width: viewWidth, height: viewHeight)
}, completion: { finished in
fromViewController?.view.removeFromSuperview()
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
}
}
class CustomInteractiveController: NSObject, UIViewControllerInteractiveTransitioning {
func startInteractiveTransition(_ transitionContext: UIViewControllerContextTransitioning) {
// I think the edge screen pan gesture goes here? Again, any advice is greatly appreciated!
}
}
最佳答案
一般来说，编写交互式自定义转场动画的流程是:
在转换开始之前，您必须给负责转换的 View Controller 一个委托(delegate)。
您将拥有一个跟踪交互式手势的手势识别器。当手势识别器识别到时，它会触发到新 View Controller 的转换。
随着转换开始，代理将被要求提供动画 Controller 。您将返回一个 UIViewControllerAnimatedTransitioning 对象。
代理还将被要求提供交互 Controller 。您将返回一个 UIViewControllerInteractiveTransitioning 对象(或
nil以防止转换是交互的)。此对象实现了startInteractiveTransition(_:)。手势识别器通过在转换上下文中不断调用
updateInteractiveTransition(_:)以及管理动画帧来继续。手势迟早会结束。此时，我们必须决定是声明转换完成还是取消。一种典型的方法是说，如果用户执行了整个手势的一半以上，则构成完成；否则，即构成取消。我们相应地完成动画。
动画现在完成了，它的完成函数被调用了。我们必须调用转换上下文的
finishInteractiveTransition或cancelInteractiveTransition，然后调用它的completeTransition(_:)并带有一个参数，说明转换是否完成或已取消。我们的
animationEnded被调用，我们清理。
在过去，你可以使用 UIPercentDrivenInteractiveTransition 对象来帮助你，但现在我总是使用 UIViewPropertyAnimator 来实现我的自定义过渡动画(iOS 10 及更高版本)；您必须首先重写整个代码才能做到这一点。我通常保留三个实例属性:UIViewPropertyAnimator、转换上下文(因为手势识别器需要引用)和一个 Bool 标志，表示这是否是交互式动画(因为相同的代码可以重复用于相同的交互式和非交互式版本动画)。
关于ios - 如何添加屏幕边缘平移手势识别器来处理此弹出动画？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46029011/