转场动画涉及到的包括导航控制器的Push动画和Pop动画，以及普通控制器的Present和Dismiss动画，主要就是通过控制器遵守UIViewControllerTransitioningDelegate，并实现对应的方法，返回一个遵守UIViewControllerAnimatedTransitioning协议的对象，而主要的动画实现就是写在这个对象当中～
- __ 如果是Push和pop动画需要再push控制器和pop时的控制器里同时实现导航控制器的代理以实现Push和Pop的动画，而Present和Dismiss动画只需要在Presnent的时候设置代理，并实现present和dismiss的协议方法就OK了 __
- __ 为了方便使用，一般会封装代理返回的动画协议对象(UIViewControllerAnimatedTransitioning)，通过之类来进一步处理各种各样的转场动画 __
//
// ViewController.m
// transitionDemo
// Copyright © 2016年 SSBun. All rights reserved.
//
#import "ViewController.h"
#import "TwoViewController.h"
#import "PushAnimator.h"
#import "PresentAnimator.h"
#import "DismissAnimator.h"
@interface ViewController ()<UIViewControllerTransitioningDelegate,UINavigationControllerDelegate>
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
self.navigationController.delegate = self;
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
TwoViewController *twoVc = [[TwoViewController alloc] init];
// Present
twoVc.transitioningDelegate = self;
twoVc.modalPresentationStyle = UIModalPresentationCustom;
[self presentViewController:twoVc
animated:YES
completion:^{
}];
// Push
// [self.navigationController pushViewController:twoVc animated:YES];
}
#pragma mark - 动画代理
- (id <UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController
animationControllerForOperation:(UINavigationControllerOperation)operation
fromViewController:(UIViewController *)fromVC
toViewController:(UIViewController *)toVC{
if ([toVC isKindOfClass:[TwoViewController class]]) {
PushAnimator *transition = [[PushAnimator alloc] init];
return transition;
}else{
return nil;
}
}
#pragma mark - 定制转场动画 (Present 与 Dismiss动画代理)
- (id<UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented
presentingController:(UIViewController *)presenting
sourceController:(UIViewController *)source {
// 推出控制器的动画
return [PresentAnimator new];
}
- (id<UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed {
DismissAnimator *dismissAnimator = [DismissAnimator new];
dismissAnimator.transitionDuration = 1.f;
// 退出控制器动画
return dismissAnimator;
}
@end
__ 可以看出协议方法主要时返回了一个遵守<UIViewControllerAnimatedTransitioning>协议的对象，所以主要的重点在实现这个对象上 __
// BaseAnimator.h
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
@interface BaseAnimator : NSObject <UIViewControllerAnimatedTransitioning>
/**
* 动画执行时间(默认值为0.5s)
*/
@property (nonatomic) NSTimeInterval transitionDuration;
/**
* == 子类重写此方法实现动画效果 ==
*
* 动画事件
*/
- (void)animateTransitionEvent;
/**
* == 在animateTransitionEvent使用才有效 ==
*
* 源头控制器
*/
@property (nonatomic, readonly, weak) UIViewController *fromViewController;
/**
* == 在animateTransitionEvent使用才有效 ==
*
* 目标控制器
*/
@property (nonatomic, readonly, weak) UIViewController *toViewController;
/**
* == 在animateTransitionEvent使用才有效 ==
*
* containerView
*/
@property (nonatomic, readonly, weak) UIView *containerView;
/**
* 动画事件结束
*/
- (void)completeTransition;
@end
// BaseAnimator.m
#import "BaseAnimator.h"
@interface BaseAnimator ()
@property (nonatomic, weak) id <UIViewControllerContextTransitioning> transitionContext;
@property (nonatomic, weak) UIViewController *fromViewController;
@property (nonatomic, weak) UIViewController *toViewController;
@property (nonatomic, weak) UIView *containerView;
@end
@implementation BaseAnimator
#pragma mark - 初始化
- (instancetype)init {
self = [super init];
if (self) {
// 默认参数设置
[self deafultSet];
}
return self;
}
- (void)deafultSet {
_transitionDuration = 0.5f;
}
#pragma mark - 动画代理
- (NSTimeInterval)transitionDuration:(id <UIViewControllerContextTransitioning>)transitionContext {
return _transitionDuration;
}
- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext {
self.fromViewController = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
self.toViewController = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
self.containerView = [transitionContext containerView];
self.transitionContext = transitionContext;
[self animateTransitionEvent];
}
- (void)animateTransitionEvent {
/* == 代码示例 ==
UIView *tmpView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
[self.containerView addSubview:self.toViewController.view];
[self.containerView addSubview:tmpView];
[UIView animateWithDuration:self.transitionDuration
delay:0.0f
usingSpringWithDamping:1 initialSpringVelocity:0.f options:0 animations:^{
tmpView.frame = CGRectMake(0, 0, 100, 100);
} completion:^(BOOL finished) {
[tmpView removeFromSuperview];
[self completeTransition];
}];
*/
}
#pragma mark -
- (void)completeTransition {
[self.transitionContext completeTransition:!self.transitionContext.transitionWasCancelled];
}
@end
__ 其中的fromViewController就是准备跳转的控制器，toViewController 就是要跳转到的控制器，containerView是整个动画的画布，需要将要跳转到的控制器的view添加到画布上执行动画，而在animateTransitionEvent中就时具体实现动画的过程了，不要忘了还要返回动画时间，用起来的时候就看各自的发挥了，可以编写子类来实现这个方法～ __
