轉(zhuǎn)場(chǎng)動(dòng)畫(huà)代碼下載主要是tabBar痒给、Navi说墨、present ；其實(shí)它里面設(shè)置到了 主要涉及到了 動(dòng)畫(huà)苍柏、交互

1 . TabBar的切換

tabbarVC 里面本身含有 <UITabBarControllerDelegate>這個(gè)代理尼斧，這個(gè)時(shí)候我們定義一個(gè) id<UITabBarControllerDelegate>類(lèi)型的實(shí)例MyTransitionTabbarDelegateManager是現(xiàn)實(shí)里面的 動(dòng)畫(huà)和交互，讓tabBarVC的delegate= MyTransitionTabbarDelegateManager對(duì)象

下面是代碼實(shí)現(xiàn)

MyTransitionTabbarDelegateManager

#import "MyTransitionTabbarDelegateManager.h"
#import "MyTransitionTabBarAnimator.h"

@interface MyTransitionTabbarDelegateManager ()

@property (nonatomic,strong) UIPercentDrivenInteractiveTransition * interactiveTransition;

@end

@implementation MyTransitionTabbarDelegateManager

- (instancetype)init {
    
    if (self = [super init]) {
        
        self.interactiveTransition = [[UIPercentDrivenInteractiveTransition alloc]init];
        self.interactive = NO;
    }
    return self;
}


//切換動(dòng)畫(huà)
- (id<UIViewControllerAnimatedTransitioning>)tabBarController:(UITabBarController *)tabBarController animationControllerForTransitionFromViewController:(UIViewController *)fromVC toViewController:(UIViewController *)toVC {
    
    NSInteger fromIndex = [tabBarController.viewControllers indexOfObject:fromVC];
    NSInteger toIndex   = [tabBarController.viewControllers indexOfObject:toVC];
    
    NSLog(@"from:%@;to:%@",fromVC,toVC);
    
    /* 確定方向 **/
    MyTransitionTabBarAnimator * animator = [[MyTransitionTabBarAnimator alloc]init];
    animator.isSlideToRight = fromIndex > toIndex?YES:NO;
    return animator;
}

//交互動(dòng)畫(huà)
- (id<UIViewControllerInteractiveTransitioning>)tabBarController:(UITabBarController *)tabBarController interactionControllerForAnimationController:(id<UIViewControllerAnimatedTransitioning>)animationController {
    
    if (self.interactive) {
        
        return self.interactiveTransition;
    }
    return nil;
}



@end

交互主要是 通過(guò)繼承 UITabBarController 來(lái)獲得一個(gè)子類(lèi) 然后在里面添加手勢(shì)

#import "MyScrollTabBarController.h"
#import "MyTransitionTabbarDelegateManager.h"

@interface MyScrollTabBarController ()

/* 處理 頁(yè)面交換 和 動(dòng)畫(huà) **/
@property (nonatomic,strong) MyTransitionTabbarDelegateManager * tabBarDelegateManager;

@end

@implementation MyScrollTabBarController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    self.tabBarDelegateManager = [[MyTransitionTabbarDelegateManager alloc]init];
    self.delegate = self.tabBarDelegateManager;
    
    UIPanGestureRecognizer * pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panAction:)];
    [self.view addGestureRecognizer:pan];
    
    NSInteger i = 0;
    for (UIViewController * vc in self.viewControllers) {
        
        NSLog(@"vc_%ld:%@",(long)i++,vc);
    }
    
}

#pragma mark - 私有方法
- (void)panAction:(UIPanGestureRecognizer *)pan {
    
    CGFloat translationX = [pan translationInView:self.view].x;
    CGFloat progress = fabs(translationX)/CGRectGetWidth(self.view.frame);
    switch (pan.state) {
        case UIGestureRecognizerStateBegan: {
            
            self.tabBarDelegateManager.interactive = YES;
            /* 
             *根據(jù)pan的速度 來(lái)判斷 滑動(dòng)的方向
             * 假設(shè) 兩點(diǎn)（x1试吁，0）棺棵，（x2，0）；
             * 如果 x1 -》x2 滑動(dòng)烛恤，如果向右邊滑動(dòng) 那么 x2 > x1;那么x1-x2<0;
             ***/
            CGFloat vX = [pan velocityInView:self.view].x;
            if (vX < 0) { // 說(shuō)明是向右邊滑動(dòng)
                
                NSInteger tmpSelectedIndex = self.selectedIndex +1;
                if (tmpSelectedIndex < self.viewControllers.count) {
                    self.selectedIndex = tmpSelectedIndex;
                }
            } else {
                
                NSInteger tmpSelectedIndex = self.selectedIndex -1;
                if (tmpSelectedIndex >= 0) {
                    self.selectedIndex = tmpSelectedIndex;
                }
            }
            
            break;
        }
        case UIGestureRecognizerStateChanged: {
            
            /* 比例的更新**/
            [self.tabBarDelegateManager.interactiveTransition updateInteractiveTransition:progress];
            break;
        }
        case UIGestureRecognizerStateEnded:
        case UIGestureRecognizerStateCancelled: {
            
            if (progress > 0.5) {
                
                [self.tabBarDelegateManager.interactiveTransition finishInteractiveTransition];
            } else {
                [self.tabBarDelegateManager.interactiveTransition cancelInteractiveTransition];
            }
            self.tabBarDelegateManager.interactive = NO;
            break;
        }
        default: {
            
            break;
        }
           
    }
}





@end

里面的 動(dòng)畫(huà)MyTransitionTabBarAnimator 主要是實(shí)現(xiàn)動(dòng)畫(huà)時(shí)間和動(dòng)畫(huà)交互 母怜，接下來(lái)就是交互 我們通過(guò) MyTransitionTabbarDelegateManager 里面的 UIPercentDrivenInteractiveTransition 主要是控制百分比、取消和完成

2 . 導(dǎo)航的切換

也是一樣我們定義一個(gè)對(duì)象遵循 <UINavigationControllerDelegate> 協(xié)議的一個(gè)對(duì)象MyNaiTransitionManager 來(lái)管理 里面的 動(dòng)畫(huà) 和 交互

3 . present的切換

也是一樣棒动，假設(shè) vc1 =present =》vc2糙申，這個(gè)時(shí)候需要實(shí)現(xiàn) vc2的代理UIViewControllerTransitioningDelegate的實(shí)例 MyVCTransionManager ,其實(shí)我們可以要知道 在vc2 中我們才能獲取到 vc1的view 和vc2的view