oc自定义present，dismiss动画

今天在写项目的广告页，之前是用uiview写的广告页，但是由于没办法在广告页出现的时候隐藏statusBar，无奈想着只能通过控制器写广告页了，因为默认present页面消失的时候是向下退出比较丑，所以打算自定义下退出动画。

刚看了几篇文章关于自定义动画的文章就总结下自定义动画，我这也只是抛砖引玉，写的比较基础，有空再写复杂的切换效果。

既然是自定义控制器切换动画，那么就必须创建一个类并且这个类要继承
UIViewControllerAnimatedTransitioning这个协议
字面意思差不多就是 控制器过渡动画 协议

先上效果图

动画.gif

这是.h文件

#import 
@interface PresentTransition : NSObject
@end

遵守这个UIViewControllerAnimatedTransitioning协议后主要要实现两个方法：
第一个方法：

- (NSTimeInterval)transitionDuration:(nullable id )transitionContext;

上面第一个方法主要是返回动画时常的没什么好讲的；

第二个方法

- (void)animateTransition:(id )transitionContext;

第二个方法就有意思了，注意context这个单词，说明这里包含我们需要做动画的很多东西

通过transitionContext我们可以获取目标控制器

    UIViewController *toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];

源控制器

UIViewController *fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];

动画时间：

NSTimeInterval duration = [self transitionDuration:transitionContext]

还有最重要的 容器，有了容器view，控制器的view才有地方显示和实现动画

UIView *containerView = [transitionContext containerView];

我这里的present动画是 源控制器从大变小，目标控制器则从右往左覆盖。
所以我这里需要拿到两个控制器的view

UIView *fromView = fromVC.view;
UIView *toView = toVC.view;

//这行代码必须加 不然目标控制器的view都不会出现
[containerView addSubview:toView];

接下来就是实现动画

[UIView animateWithDuration:duration animations:^{
        
        //        fromView.x = containerView.width * (1 - scale) / 2;
        //        fromView.y = containerView.height * (1 - scale) / 2;
        //        fromView.width = containerView.width * scale;
        //        fromView.height = containerView.height * scale;
        
        toView.x = containerView.x;
        fromView.transform = CGAffineTransformMakeScale(0.9, 0.9);
        
    } completion:^(BOOL finished) {
        fromView.transform = CGAffineTransformMakeScale(1, 1);
        [transitionContext completeTransition:YES];
    }];

所以PresentTransition.m文件的代码就是

#import "PresentTransition.h"
@implementation PresentTransition

- (NSTimeInterval)transitionDuration:(id)transitionContext{
    return 0.4;
}

- (NSTimeInterval)transitionDuration:(id)transitionContext{
    return 0.4;
}

- (void)animateTransition:(id)transitionContext{

    UIViewController *toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    UIViewController *fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    
    UIView *containerView = [transitionContext containerView];
    NSLog(@"%@", containerView);
    UIView *fromView = fromVC.view;
    UIView *toView = toVC.view;
    
    toView.x = containerView.width;
    
    [containerView addSubview:toView];
    
    NSTimeInterval duration = [self transitionDuration:transitionContext];
    [UIView animateWithDuration:duration animations:^{
        
        //        fromView.x = containerView.width * (1 - scale) / 2;
        //        fromView.y = containerView.height * (1 - scale) / 2;
        //        fromView.width = containerView.width * scale;
        //        fromView.height = containerView.height * scale;
        
        toView.x = containerView.x;
        fromView.transform = CGAffineTransformMakeScale(0.9, 0.9);
        
    } completion:^(BOOL finished) {
        fromView.transform = CGAffineTransformMakeScale(1, 1);
        [transitionContext completeTransition:YES];
    }];
}

自定义动画到这里就结束了，接下来是怎么用：
首先在源控制器.m 遵守协议，.h不变

@interface ViewController ()

然后实现方法 和 代理

- (void)presentBtnClicked{
    
    ZCCSecondViewController *secondVC = [[ZCCSecondViewController alloc] init];
    secondVC.transitioningDelegate = self;//
    [self presentViewController:secondVC animated:YES completion:nil];
}

- (id)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source{
    
    PresentTransition *transition = [[PresentTransition alloc] init];
    transition.transitionType = ZCCTransitionTypePresent;
    return transition;
}

目标控制器操作 .m文件 这里我还写了返回来的动画 所以我目标控制器是这么写的

@interface ZCCSecondViewController ()
@end

- (void)dismissClick{
    
    self.transitioningDelegate = self;
    [self dismissViewControllerAnimated:YES completion:nil];
}
- (id)animationControllerForDismissedController:(UIViewController *)dismissed{
    PresentTransition *pushAnimation = [[PresentTransition alloc] init];
    pushAnimation.transitionType = ZCCTransitionTypeDismiss;
    return pushAnimation;
}

自定义动画的完整版代码如下

.h文件

#import 

typedef NS_ENUM(NSUInteger, ZCCTransitionType){
    
    ZCCTransitionTypePresent = 0,
    ZCCTransitionTypeDismiss,
    ZCCTransitionTypePush,
    ZCCTransitionTypePop,
};

@interface PresentTransition : NSObject

@property (nonatomic, assign)ZCCTransitionType transitionType;

@end

.m文件

//
//  PresentTransition.m
//  MOSOBOStudent
//
//  Created by 章程程 on 2018/4/2.
//  Copyright © 2018年 zcc. All rights reserved.
//

#import "PresentTransition.h"
#import "ZCCCommon.h"
@implementation PresentTransition

- (NSTimeInterval)transitionDuration:(id)transitionContext{
    return 0.4;
}

- (void)animateTransition:(id)transitionContext{
    
    switch (_transitionType) {
        case ZCCTransitionTypePresent:
            {
                [self presentAnimation:transitionContext];
            }
            break;
        case ZCCTransitionTypeDismiss:
            {
                [self dismissAnimation:transitionContext];
            }
            break;
        case ZCCTransitionTypePush:
            {
                
            }
            break;
        case ZCCTransitionTypePop:
            {
                
            }
            break;
        default:
            break;
    }
    
}

- (void)presentAnimation:(id)transitionContext{
    
    UIViewController *toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    UIViewController *fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    
    UIView *containerView = [transitionContext containerView];
    containerView.backgroundColor = [UIColor whiteColor];
    NSLog(@"%@", containerView);
    UIView *fromView = fromVC.view;
    UIView *toView = toVC.view;
    
    toView.x = containerView.width;
    
    [containerView addSubview:toView];
    
    NSTimeInterval duration = [self transitionDuration:transitionContext];
    [UIView animateWithDuration:duration animations:^{
        
        //        fromView.x = containerView.width * (1 - scale) / 2;
        //        fromView.y = containerView.height * (1 - scale) / 2;
        //        fromView.width = containerView.width * scale;
        //        fromView.height = containerView.height * scale;
        
        toView.x = containerView.x;
        fromView.transform = CGAffineTransformMakeScale(0.9, 0.9);
        
    } completion:^(BOOL finished) {
        fromView.transform = CGAffineTransformMakeScale(1, 1);
        [transitionContext completeTransition:YES];
    }];
}

- (void)dismissAnimation:(id)transitionContext{
    
    UIViewController *toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
    UIViewController *fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
    
    UIView *containerView = [transitionContext containerView];
    NSLog(@"%@", containerView);
    UIView *fromView = fromVC.view;
    UIView *toView = toVC.view;
    
    [containerView addSubview:toView];
    
    [containerView bringSubviewToFront:fromVC.view];
    
    toView.transform = CGAffineTransformMakeScale(0.9, 0.9);
    
    NSTimeInterval duration = [self transitionDuration:transitionContext];
    
    [UIView animateWithDuration:duration animations:^{
        
        fromView.x = containerView.width;
        toView.transform = CGAffineTransformMakeScale(1.0, 1.0);
        
    } completion:^(BOOL finished) {
        [transitionContext completeTransition:YES];
    }];
    
}
    
@end