我一直在关注一些教程来创建自定义动画，同时从一个视图过渡到另一个视图。
我从这里使用自定义 segue 的测试项目工作正常，但有人告诉我不再鼓励在自定义 segue 中进行自定义动画，我应该使用UIViewControllerAnimatedTransitioning.
我遵循了几个使用此协议的教程，但它们都是关于模态表示的（例如本教程）。
我正在尝试做的是导航控制器树中的推送转场，但是当我尝试对显示（推）转场做同样的事情时，它就不再起作用了。
请告诉我在导航控制器中从一个视图到另一个视图的自定义过渡动画的正确方法。
无论如何我可以对所有过渡动画使用一种方法吗？如果有一天我想做同样的动画，但最终不得不复制两次代码来处理模态与控制器的转换，那会很尴尬。
要使用导航控制器 ( UINavigationController) 进行自定义转换，您应该：
定义您的视图控制器以符合UINavigationControllerDelegate协议。例如，您可以在视图控制器的.m文件中包含一个私有类扩展，以指定与此协议的一致性：
@interface ViewController () <UINavigationControllerDelegate>
@end
确保您实际上将视图控制器指定为导航控制器的委托：
- (void)viewDidLoad {
[super viewDidLoad];
self.navigationController.delegate = self;
}
animationControllerForOperation在您的视图控制器中实现：
- (id<UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController
animationControllerForOperation:(UINavigationControllerOperation)operation
fromViewController:(UIViewController*)fromVC
toViewController:(UIViewController*)toVC
{
if (operation == UINavigationControllerOperationPush)
return [[PushAnimator alloc] init];
if (operation == UINavigationControllerOperationPop)
return [[PopAnimator alloc] init];
return nil;
}
为推送和弹出动画实现动画师，例如：
@interface PushAnimator : NSObject <UIViewControllerAnimatedTransitioning>
@end
@interface PopAnimator : NSObject <UIViewControllerAnimatedTransitioning>
@end
@implementation PushAnimator
- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext
{
return 0.5;
}
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{
UIViewController* toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
[[transitionContext containerView] addSubview:toViewController.view];
toViewController.view.alpha = 0.0;
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
toViewController.view.alpha = 1.0;
} completion:^(BOOL finished) {
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
}];
}
@end
@implementation PopAnimator
- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext
{
return 0.5;
}
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{
UIViewController* toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIViewController* fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
[[transitionContext containerView] insertSubview:toViewController.view belowSubview:fromViewController.view];
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
fromViewController.view.alpha = 0.0;
} completion:^(BOOL finished) {
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
}];
}
@end
这确实会淡入淡出过渡，但您应该随意自定义您认为合适的动画。
如果你想处理交互手势（例如像原生的从左到右滑动来弹出），你必须实现一个交互控制器：
为交互控制器定义一个属性（一个符合 的对象UIViewControllerInteractiveTransitioning）：
@property (nonatomic, strong) UIPercentDrivenInteractiveTransition *interactionController;
这UIPercentDrivenInteractiveTransition是一个很好的对象，它可以根据手势的完成程度来完成更新自定义动画的繁重工作。
将手势识别器添加到您的视图中。这里我只是实现了左手势识别器来模拟弹出：
UIScreenEdgePanGestureRecognizer *edge = [[UIScreenEdgePanGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipeFromLeftEdge:)];
edge.edges = UIRectEdgeLeft;
[view addGestureRecognizer:edge];
实现手势识别器处理程序：
/** Handle swipe from left edge
*
* This is the "action" selector that is called when a left screen edge gesture recognizer starts.
*
* This will instantiate a UIPercentDrivenInteractiveTransition when the gesture starts,
* update it as the gesture is "changed", and will finish and release it when the gesture
* ends.
*
* @param gesture The screen edge pan gesture recognizer.
*/
- (void)handleSwipeFromLeftEdge:(UIScreenEdgePanGestureRecognizer *)gesture {
CGPoint translate = [gesture translationInView:gesture.view];
CGFloat percent = translate.x / gesture.view.bounds.size.width;
if (gesture.state == UIGestureRecognizerStateBegan) {
self.interactionController = [[UIPercentDrivenInteractiveTransition alloc] init];
[self popViewControllerAnimated:TRUE];
} else if (gesture.state == UIGestureRecognizerStateChanged) {
[self.interactionController updateInteractiveTransition:percent];
} else if (gesture.state == UIGestureRecognizerStateEnded) {
CGPoint velocity = [gesture velocityInView:gesture.view];
if (percent > 0.5 || velocity.x > 0) {
[self.interactionController finishInteractiveTransition];
} else {
[self.interactionController cancelInteractiveTransition];
}
self.interactionController = nil;
}
}
在您的导航控制器委托中，您还必须实现interactionControllerForAnimationController委托方法
- (id<UIViewControllerInteractiveTransitioning>)navigationController:(UINavigationController *)navigationController
interactionControllerForAnimationController:(id<UIViewControllerAnimatedTransitioning>)animationController {
return self.interactionController;
}
如果你用谷歌搜索“UINavigationController 自定义转换教程”，你会得到很多点击。或观看WWDC 2013 自定义转场视频。
您可能想在之前添加以下代码addSubview
toViewController.view.frame = [transitionContext finalFrameForViewController:toViewController];
从另一个问题custom-transition-for-push-animation-with-navigationcontroller-on-ios-9
来自 Apple 的 finalFrameForViewController 文档：
返回指定视图控制器视图的结束框架矩形。
该方法返回的矩形表示过渡结束时对应视图的大小。对于演示期间覆盖的视图，此方法返回的值可能是 CGRectZero 但它也可能是有效的框架矩形。
使用 Rob's & Q i 的完美答案，这里是简化的 Swift 代码，对 .push 和 .pop 使用相同的淡入淡出动画：
extension YourViewController: UINavigationControllerDelegate {
func navigationController(_ navigationController: UINavigationController,
animationControllerFor operation: UINavigationControllerOperation,
from fromVC: UIViewController,
to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
//INFO: use UINavigationControllerOperation.push or UINavigationControllerOperation.pop to detect the 'direction' of the navigation
class FadeAnimation: NSObject, UIViewControllerAnimatedTransitioning {
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.5
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let toViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)
if let vc = toViewController {
transitionContext.finalFrame(for: vc)
transitionContext.containerView.addSubview(vc.view)
vc.view.alpha = 0.0
UIView.animate(withDuration: self.transitionDuration(using: transitionContext),
animations: {
vc.view.alpha = 1.0
},
completion: { finished in
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
})
} else {
NSLog("Oops! Something went wrong! 'ToView' controller is nill")
}
}
}
return FadeAnimation()
}
}
不要忘记在 YourViewController 的 viewDidLoad() 方法中设置委托：
override func viewDidLoad() {
//...
self.navigationController?.delegate = self
//...
}
它适用于 swift 3 和 4
@IBAction func NextView(_ sender: UIButton) {
let newVC = self.storyboard?.instantiateViewControllerWithIdentifier(withIdentifier: "NewVC") as! NewViewController
let transition = CATransition()
transition.duration = 0.5
transition.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
transition.type = kCATransitionPush
transition.subtype = kCAGravityLeft
//instead "kCAGravityLeft" try with different transition subtypes
self.navigationController?.view.layer.add(transition, forKey: kCATransition)
self.navigationController?.pushViewController(newVC, animated: false)
}