封装了一个优雅的iOS全屏侧滑返回工具

思路
添加一个全屏返回手势，UIPangesturerecognizer,
1 手势开始
在手势开始响应的时候，将navigationController的delegate代理设置为工具类，在工具类中执行代理方法，- (nullable id )navigationController:(UINavigationController *)navigationController
和 - (nullable id )navigationController:(UINavigationController *)navigationController

都返回为侧滑工具对象，然后侧滑工具实现

• (NSTimeInterval)transitionDuration:(nullable id )transitionContext {
  和 - (void)animateTransition:(id)transitionContext
  方法 ， 并实现 - (void)startInteractiveTransition:(id )transitionContext {
  方法，

2 手势改变
计算滑动比例，我们以超过200就算1，根据translationInView 计算滑动比例

在手势的改变的状态下，
通过 UIView *toView = [self.transitionContext viewForKey:UITransitionContextToViewKey];
UIView *fromView = [self.transitionContext viewForKey:UITransitionContextFromViewKey];
UIView *containerView = self.transitionContext.containerView;
方法获取到要退回到的视图和来源视图，并修改frame，
达到两个视图移动的效果

3 手势结束，根据滑动距离和速度确定是完成返回还是取消返回

4 注意要添加弹簧动画，使交互效果更流畅优雅

效果图

代码如下

@interface LBTransitionManager : NSObject@property (nonatomic, weak) UINavigationController *navigationController;+ (instancetype)shareManager;- (UIPanGestureRecognizer *)addPanGestureRecognizerToViewControllerIfNeeded:(UIViewController *)viewController ;@end

//
//  LBTransitionManager.m
//  TEXT
//
//  Created by mac on 2025/3/30.
//#import "LBTransitionManager.h"
#import <UIKit/UIKit.h>
#import "LBTransitionInteractivePopLinearAnimation.h"@interface LBTransitionManager () <UINavigationControllerDelegate,
UIViewControllerAnimatedTransitioning,
UIViewControllerInteractiveTransitioning>@property (nonatomic, strong) LBTransitionInteractivePopLinearAnimation *currentInteractiveAnimation;@property (nonatomic, weak) UIPanGestureRecognizer *currentPanGestureRecognizer;@property (nonatomic, strong) id <UIViewControllerContextTransitioning> transitionContext;@end@implementation LBTransitionManager+ (instancetype)shareManager
{static dispatch_once_t onceToken;static LBTransitionManager *shareManager = nil;dispatch_once(&onceToken, ^{shareManager = [[self alloc] init];});return shareManager;;
}- (UIPanGestureRecognizer *)addPanGestureRecognizerToViewControllerIfNeeded:(UIViewController *)viewController {UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];[viewController.view addGestureRecognizer:panGestureRecognizer];return panGestureRecognizer;
}#pragma mark - UINavigationControllerDelegate- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {}- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated {}- (nullable id <UIViewControllerInteractiveTransitioning>)navigationController:(UINavigationController *)navigationControllerinteractionControllerForAnimationController:(id <UIViewControllerAnimatedTransitioning>)animationController {return self;
}- (nullable id <UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationControlleranimationControllerForOperation:(UINavigationControllerOperation)operationfromViewController:(UIViewController *)fromVCtoViewController:(UIViewController *)toVC {return self;
}#pragma mark - UIViewControllerAnimationTransitioning- (NSTimeInterval)transitionDuration:(nullable id <UIViewControllerContextTransitioning>)transitionContext {NSTimeInterval transitionDuration = 0.4;if ([self.currentInteractiveAnimation respondsToSelector:@selector(transitionDuration)]) {transitionDuration = [self.currentInteractiveAnimation transitionDuration];}return transitionDuration;
}- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{UIViewController *fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];UIViewController *toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
}#pragma mark - UIViewControllerInteractiveTransitioning- (void)startInteractiveTransition:(id <UIViewControllerContextTransitioning>)transitionContext {NSLog(@"ttttttt startInteractiveTransition, current pan: %@", self.currentPanGestureRecognizer);[self updateViewsInteractionWithTransitionContext:transitionContext isEnabled:NO];id<LBTransitionAnimationProtocol> animation = [[LBTransitionInteractivePopLinearAnimation alloc] init];[animation prepareTransitionWithTransitionContext:transitionContext];if (self.currentPanGestureRecognizer == nil) {[animation finishTransitionIsCancel:YES completion:^(BOOL finished, BOOL isCancel, id<UIViewControllerContextTransitioning>  _Nonnull transitionContext) {[self finishInteractiveTransitionWithTransitionContext:transitionContext isCancel:isCancel isAnimationFinished:finished];[self updateViewsInteractionWithTransitionContext:transitionContext isEnabled:YES];}];} else {self.currentInteractiveAnimation = animation;}
}#pragma mark - action- (void)handlePan:(id)sender {if (![sender isKindOfClass:[UIPanGestureRecognizer class]]) return;UIPanGestureRecognizer *panGestureRecognizer = sender;CGPoint velocity = [panGestureRecognizer velocityInView:panGestureRecognizer.view.superview];CGPoint translation = [panGestureRecognizer translationInView:panGestureRecognizer.view.superview];CGFloat percentComplete = [self percentCompleteWithTranslation:translation];UIResponder *nextResponder = panGestureRecognizer.view.nextResponder;switch (panGestureRecognizer.state) {case UIGestureRecognizerStateBegan: {NSLog(@"ttttttt pan pop state began");CGFloat velocityX = velocity.x;CGFloat velocityY = velocity.y;if (velocityX == 0.0) {panGestureRecognizer.enabled = NO;panGestureRecognizer.enabled = YES;return;}self.currentPanGestureRecognizer = panGestureRecognizer;UINavigationController *navigationController = self.navigationController;id<UINavigationControllerDelegate> navigationControllerDelegate = navigationController.delegate;navigationController.delegate = self;NSLog(@"LIVDetailTransitionManager navigationControllerDelegate: %@", navigationController.delegate);[navigationController popViewControllerAnimated:YES];navigationController.delegate = navigationControllerDelegate;}break;case UIGestureRecognizerStateChanged: {NSLog(@"这里的animation %@", self.currentInteractiveAnimation);BOOL finishInstantly = [self.currentInteractiveAnimation updateTransitionWithPercentComplete:percentComplete translation:translation];if (finishInstantly) {self.currentPanGestureRecognizer.state = UIGestureRecognizerStateEnded;}}break;case UIGestureRecognizerStateCancelled:case UIGestureRecognizerStateFailed: {NSLog(@"ttttttt pan pop state cancelled, failed, started: %@", self.currentInteractiveAnimation);self.currentPanGestureRecognizer = nil;[self.currentInteractiveAnimation finishTransitionIsCancel:YES completion:^(BOOL finished, BOOL isCancel, id<UIViewControllerContextTransitioning> transitionContext) {[self finishInteractiveTransitionWithTransitionContext:transitionContext isCancel:isCancel isAnimationFinished:finished];}];} break;case UIGestureRecognizerStateEnded: {BOOL isTransitionMadeProgress = percentComplete > 0.1;BOOL isPanRight = velocity.x > 0.0;BOOL shouldComplete = NO;shouldComplete = (isTransitionMadeProgress && isPanRight) || velocity.x > 100.0;NSLog(@"ttttttt pan pop state end: %d, %d, %d, %@", isTransitionMadeProgress, isPanRight, shouldComplete, self.currentInteractiveAnimation);self.currentPanGestureRecognizer = nil;__weak typeof(self) weakSelf = self;[self.currentInteractiveAnimation finishTransitionIsCancel:!shouldComplete completion:^(BOOL finished, BOOL isCancel, id<UIViewControllerContextTransitioning> transitionContext) {[self finishInteractiveTransitionWithTransitionContext:transitionContext isCancel:isCancel isAnimationFinished:finished];[self updateViewsInteractionWithTransitionContext:transitionContext isEnabled:YES];}];} break;default:break;}
}- (CGFloat)percentCompleteWithTranslation:(CGPoint)translation {CGFloat translationX = translation.x;CGFloat translationXRangeMin = 0.0;CGFloat translationXRangeMax = 200.0;if (translationX < translationXRangeMin) {return 0.0;} else if (translationX > translationXRangeMax) {return 1.0;} else {return (translationX - translationXRangeMin) / (translationXRangeMax - translationXRangeMin);}
}- (void)finishInteractiveTransitionWithTransitionContext:(id<UIViewControllerContextTransitioning>)transitionContext isCancel:(BOOL)isCancel isAnimationFinished:(BOOL)isAnimationFinished {NSLog(@"ttttttt finish interactive transition: %d, %d", isCancel, isAnimationFinished);id<LBTransitionAnimationProtocol> currentInteractiveAnimation = self.currentInteractiveAnimation;self.currentInteractiveAnimation = nil;if (isCancel) {[transitionContext cancelInteractiveTransition];} else {[transitionContext finishInteractiveTransition];}[transitionContext completeTransition:!isCancel];
}- (void)updateViewsInteractionWithTransitionContext:(id<UIViewControllerContextTransitioning>)transitionContext isEnabled:(BOOL)isEnabled {UIViewController *fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];UIViewController *toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];fromViewController.view.userInteractionEnabled = isEnabled;toViewController.view.userInteractionEnabled = isEnabled;
}@end

//
//  LBTransitionInteractivePopAnimation.h
//  TEXT
//
//  Created by mac on 2025/3/30.//#import <Foundation/Foundation.h>
#import "LBTransitionAnimationProtocol.h"NS_ASSUME_NONNULL_BEGIN@interface LBTransitionInteractivePopLinearAnimation : NSObject <LBTransitionAnimationProtocol>@endNS_ASSUME_NONNULL_END

//
//  LBTransitionInteractivePopAnimation.m
//  TEXT
//
//  Created by mac on 2025/3/30.
//#import "LBTransitionInteractivePopLinearAnimation.h"
#import <UIKit/UIKit.h>
#import "UIView+LBFrame.h"@interface LBTransitionInteractivePopLinearAnimation ()@property (strong, nonatomic) id<UIViewControllerContextTransitioning> transitionContext;@property (strong, nonatomic) UIView *containerView;@property (strong, nonatomic) UIView *animationContainerView;@end@implementation LBTransitionInteractivePopLinearAnimation- (instancetype)init{self = [super init];if (self == nil) return nil;return self;
}#pragma mark - Transition- (NSTimeInterval)transitionDuration {return 0.4;
}- (void)prepareTransitionWithTransitionContext:(id<UIViewControllerContextTransitioning>)transitionContext {self.transitionContext = transitionContext;UIView *containerView = transitionContext.containerView;containerView.backgroundColor = UIColor.clearColor;self.containerView = containerView;UIView *toView = [transitionContext viewForKey:UITransitionContextToViewKey];toView.frame = containerView.bounds;toView.x = -(containerView.width / 4.0);[self.containerView addSubview:toView];UIView *fromView = [transitionContext viewForKey:UITransitionContextFromViewKey];fromView.frame = containerView.bounds;[self.containerView addSubview:fromView];
}- (BOOL)updateTransitionWithPercentComplete:(CGFloat)percentComplete translation:(CGPoint)translation {UIView *toView = [self.transitionContext viewForKey:UITransitionContextToViewKey];UIView *fromView = [self.transitionContext viewForKey:UITransitionContextFromViewKey];UIView *containerView = self.transitionContext.containerView;CGFloat toViewInitialX = containerView.x - (containerView.width / 4.0);CGFloat toViewMaxX = containerView.x;CGFloat fromViewInitialX = containerView.x;CGFloat fromViewMaxX = containerView.width;toView.x = containerView.x - (containerView.width / 4.0) + translation.x * 0.25;fromView.x = containerView.x + translation.x;if (toView.x < toViewInitialX) {toView.x = toViewInitialX;}if (toView.x > toViewMaxX) {toView.x = toViewMaxX;}if (fromView.x < fromViewInitialX) {fromView.x = fromViewInitialX;}if (fromView.x > fromViewMaxX) {fromView.x = fromViewMaxX;}[self.transitionContext updateInteractiveTransition:percentComplete];return NO;
}- (void)finishTransitionIsCancel:(BOOL)isCancel completion:(LIVDetailTransitionAnimationCompletion)completion {UIView *toView = [self.transitionContext viewForKey:UITransitionContextToViewKey];UIView *fromView = [self.transitionContext viewForKey:UITransitionContextFromViewKey];UIView *containerView = self.transitionContext.containerView;CGFloat toViewInitialX = containerView.x - (containerView.width / 4.0);CGFloat toViewMaxX = containerView.x;CGFloat fromViewInitialX = containerView.x;CGFloat fromViewMaxX = containerView.width;[UIView animateWithDuration:[self transitionDuration] delay:0.0 usingSpringWithDamping:1.0 initialSpringVelocity:0.0 options:UIViewAnimationOptionLayoutSubviews | UIViewAnimationOptionCurveLinear animations:^{if (isCancel) {toView.x = toViewInitialX;fromView.x = fromViewInitialX;} else {toView.x = toViewMaxX;fromView.x = fromViewMaxX;}} completion:^(BOOL finished) {NSLog(@"interactive pop linear animation completion: %d, %d", finished, isCancel);if (completion != nil) {completion(finished, isCancel, self.transitionContext);}}];
}@end

//
//  LBTransitionAnimationProtocol.h
//  TEXT
//
//  Created by mac on 2025/3/30.
//#ifndef LBTransitionAnimationProtocol_h
#define LBTransitionAnimationProtocol_h
#import <UIKit/UIKit.h>typedef void(^LIVDetailTransitionAnimationCompletion)(BOOL finished, BOOL isCancel, id<UIViewControllerContextTransitioning> transitionContext);@protocol LBTransitionAnimationProtocol <NSObject>- (void)prepareTransitionWithTransitionContext:(id<UIViewControllerContextTransitioning>)transitionContext;
- (BOOL)updateTransitionWithPercentComplete:(CGFloat)percentComplete translation:(CGPoint)translation; // 更新当前动画进度，返回 YES 代表需要马上结束转场
- (void)finishTransitionIsCancel:(BOOL)isCancel completion:(LIVDetailTransitionAnimationCompletion)completion;- (NSTimeInterval)transitionDuration;@end#endif /* LBTransitionAnimationProtocol_h */