通过这几天的学习，我尝试实现了四个效果，废话不多说，先上效果图：
DEMO ONE：一个神奇移动效果push动画，支持手势pop
神奇效果.gif
DEMO TWO：一个弹性的present动画，支持手势present和dismiss
弹性present.gif
DEMO THREE：一个翻页push效果，支持手势PUSH和POP
翻页效果.gif
DEMO FOUR：一个小圆点扩散present效果，支持手势dimiss
小圆点扩散.gif
准备
从iOS7开始,苹果提供了自定义转场的API,模态推送present和dismiss,导航控制器的push和pop,标签控制器的控制器切换都可以自定义转场了.
1.我们需要自定义一个遵循的
// 返回动画事件
- (NSTimeInterval)transitionDuration:(nullable id )transitionContext;
// 所有的过渡动画事务都在这个方法里面完成
- (void)animateTransition:(id )transitionContext;
2.我们还需要自定义一个继承于UIPercentDrivenInteractiveTransition的手势过渡管理对象，我把它成为百分比手势过渡管理对象，因为动画的过程是通过百分比控制的
3.成为相应的代理，实现相应的代理方法，返回我们前两步自定义的对象就OK了 ！
模态推送需要实现如下4个代理方法，iOS8新的那个方法我暂时还没有发现它的用处，所以暂不讨论.
//返回一个管理present动画过渡的对象
- (nullable id )animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source;
//返回一个管理dismiss动画过渡的对象
- (nullable id )animationControllerForDismissedController:(UIViewController *)dismissed;
//返回一个管理present手势过渡的对象
- (nullable id )interactionControllerForPresentation:(id )animator;
//返回一个管理dismiss动画过渡的对象
- (nullable id )interactionControllerForDismissal:(id )animator;
导航控制器实现如下2个代理方法
//返回转场动画过渡管理对象
- (nullable id )navigationController:(UINavigationController *)navigationController
interactionControllerForAnimationController:(id ) animationController NS_AVAILABLE_IOS(7_0);
//返回手势过渡管理对象
- (nullable id )navigationController:(UINavigationController *)navigationController
animationControllerForOperation:(UINavigationControllerOperation)operation
fromViewController:(UIViewController *)fromVC
toViewController:(UIViewController *)toVC NS_AVAILABLE_IOS(7_0);
标签控制器也有相应的两个方法
//返回转场动画过渡管理对象
- (nullable id )tabBarController:(UITabBarController *)tabBarController
interactionControllerForAnimationController: (id )animationController NS_AVAILABLE_IOS(7_0);
//返回手势过渡管理对象
- (nullable id )tabBarController:(UITabBarController *)tabBarController
animationControllerForTransitionFromViewController:(UIViewController *)fromVC
toViewController:(UIViewController *)toVC NS_AVAILABLE_IOS(7_0);
4.如果看着这些常常的代理方法名头疼的话，没关系，先在demo中用起来吧，慢慢就习惯了，其实哪种自定义转场都只需要这3个步骤，如果不需要手势控制，步骤2还可以取消，现在就让我们动手来实现效果吧
Let's go!
DEMO ONE：神奇移动效果
1.我们首先创建2个控制器，为了方便我称做present操作的为vc1、被present的为vc2，点击一个控制器上的按钮可以push出另一个控制器.
2.创建一个手势过渡管理的类，我这里是PEInteractiveTransition,因为无论哪一种转场，手势控制的实质都是一样的，我干脆就把这个手势过渡管理的类封装了一下，具体可以在.h文件里面查看，在接下来的三个转场效果中我们都可以便捷的是使用它：
PEInteractiveTransition.h
typedef void(^GestureConfig)();
//手势转场类型
typedef NS_ENUM(NSUInteger,PEInteractiveTransitionType){
PEInteractiveTransitionTypePresent = 0,
PEInteractiveTransitionTypeDismiss,
PEInteractiveTransitionTypePush,
PEInteractiveTransitionTypePop
};
//手势方向
typedef NS_ENUM(NSUInteger,PEInteractiveTransitionGestureDirection){
PEInteractiveTransitionGestureDirectionLeft = 0,
PEInteractiveTransitionGestureDirectionRight,
PEInteractiveTransitionGestureDirectionUp,
PEInteractiveTransitionGestureDirectionDown
};
@interface PEInteractiveTransition : UIPercentDrivenInteractiveTransition
/** 记录是否开始手势,判断pop操作是手势出发还是返回键出发 */
@property (nonatomic, assign)BOOL interation;
/** 触发手势present的时候config,在config中初始化并present需要弹出的控制器 */
@property (nonatomic, copy)GestureConfig presentConfig;
/** 触发手势push的时候config,在config中初始化并push需要弹出的控制器 */
@property (nonatomic, copy)GestureConfig pushConfig;
#pragma mark - ---初始化方法---
+ (instancetype)interactiveTransitionWithTransitionType:(PEInteractiveTransitionType)type GestureDirection:(PEInteractiveTransitionGestureDirection)direction;
- (instancetype)initWithTransitionType:(PEInteractiveTransitionType)type GestureDirection:(PEInteractiveTransitionGestureDirection)direction;
/** 给传入控制器添加手势*/
- (void)addPanGestureForViewController:(UIViewController *)viewController;
@end
PEInteractiveTransition.m
#import "PEInteractiveTransition.h"
@interface PEInteractiveTransition()
/** 传入的ViewController */
@property (nonatomic, weak)UIViewController *vc;
/** 手势方向 */
@property (nonatomic, assign)PEInteractiveTransitionGestureDirection direction;
/** 手势类型 */
@property (nonatomic, assign)PEInteractiveTransitionType type;
@end
@implementation PEInteractiveTransition
+ (instancetype)interactiveTransitionWithTransitionType:(PEInteractiveTransitionType)type GestureDirection:(PEInteractiveTransitionGestureDirection)direction
{
return [[self alloc] initWithTransitionType:type GestureDirection:direction];
}
- (instancetype)initWithTransitionType:(PEInteractiveTransitionType)type GestureDirection:(PEInteractiveTransitionGestureDirection)direction{
self = [super init];
if (self) {
_direction = direction;
_type = type;
}
return self;
}
- (void)addPanGestureForViewController:(UIViewController *)viewController
{
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
self.vc = viewController;
[viewController.view addGestureRecognizer:pan];
}
/**
* 手势过渡过程
*
* @param pan 添加的手势
*/
- (void)handleGesture:(UIPanGestureRecognizer *)pan
{
//手势百分比 初始化为0 向上和向右滑动 距离是负的 所以前面加负号 这样负负得正
CGFloat persent = 0;
switch (_direction) {
case PEInteractiveTransitionGestureDirectionUp:{
CGFloat transitionY = -[pan translationInView:pan.view].y;
persent = transitionY / pan.view.frame.size.width;
}
break;
case PEInteractiveTransitionGestureDirectionRight:{
CGFloat transitionR = [pan translationInView:pan.view].x;
persent = transitionR / pan.view.frame.size.width;
}
break;
case PEInteractiveTransitionGestureDirectionDown:{
CGFloat transitionD = [pan translationInView:pan.view].y;
persent = transitionD / pan.view.frame.size.width;
}
break;
case PEInteractiveTransitionGestureDirectionLeft:{
CGFloat transitionL = -[pan translationInView:pan.view].x;
persent = transitionL / pan.view.frame.size.width;
}
break;
default:
break;
}
switch (pan.state) {
case UIGestureRecognizerStateBegan:{
//手势开始的时候标记手势状态,并开始相应的事件
self.interation = YES;
[self startGesture];
}
break;
case UIGestureRecognizerStateChanged:{
//手势过程中,通过updateInteractiveTransition设置pop过程进行的百分比
[self updateInteractiveTransition:persent];
}
break;
case UIGestureRecognizerStateEnded:{
//手势完成后结束标记并且判断移动的距离是否过半,过则finishInteractiveTransition完成转场操作,否则取消转场操作
self.interation = NO;
if (persent > 0.5) {
[self finishInteractiveTransition];
}else {
[self cancelInteractiveTransition];
}
}
break;
default:
break;
}
}
- (void)startGesture
{
switch (_type) {
case PEInteractiveTransitionTypePresent:{
if (_presentConfig) {
_presentConfig();
}
}
break;
case PEInteractiveTransitionTypeDismiss:{
[_vc dismissViewControllerAnimated:YES completion:nil];
}
break;
case PEInteractiveTransitionTypePush:{
if (_pushConfig) {
_pushConfig();
}
}
break;
case PEInteractiveTransitionTypePop:{
[_vc.navigationController popViewControllerAnimated:YES];
}
break;
default:
break;
}
}
@end
3.创建神奇效果的具体动画代理
PENaviTransition.h
typedef NS_ENUM(NSUInteger, PENaviTransitionType){
PENaviTransitionTypePush = 0,
PENaviTransitionTypePop
};
@interface PENaviTransition : NSObject
+ (instancetype)transitionWithType:(PENaviTransitionType)type;
- (instancetype)initWithTransitionType:(PENaviTransitionType)type;
@end
PENaviTransition.m主要实现一个动画时长方法和一个push动画和一个pop动画
/**
* 动画时长
*/
- (NSTimeInterval)transitionDuration:(id)transitionContext
{
return 0.75;
}
/**
* 如何执行过渡动画
*/
- (void)animateTransition:(id)transitionContext
{
switch (_type) {
case PENaviTransitionTypePush:
[self doPushAnimation:transitionContext];
break;
case PENaviTransitionTypePop:
[self doPopAnimation:transitionContext];
break;
default:
break;
}
}
/**
* 执行push过渡动画
*/
- (void)doPushAnimation:(id)transitionContext
{
PEMagicMoveController *fromVC = (PEMagicMoveController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
PEMagicMovePushController *toVC = (PEMagicMovePushController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
//拿到当前点击的cell的imageView
PEMagicMoveCell *cell = (PEMagicMoveCell *)[fromVC.collectionView cellForItemAtIndexPath:fromVC.clickIndex];
UIView *containerView = [transitionContext containerView];
UIView *tempView = [cell.imageV snapshotViewAfterScreenUpdates:NO];
//将点击的cell截图作为临时View的内容 并将坐标系转化成push控制器种的坐标
tempView.frame = [cell.imageV convertRect:cell.imageV.bounds toView:containerView];
//设置动画前的各个控件的状态
cell.imageV.hidden = YES;
toVC.view.alpha = 0;
toVC.imageView.hidden = YES;
//tempView添加到containerView中保证在最前方,所以后添加
[containerView addSubview:toVC.view];
[containerView addSubview:tempView];
//开始push动画
[UIView animateWithDuration:[self transitionDuration:transitionContext] delay:0.0 usingSpringWithDamping:0.55 initialSpringVelocity:1/0.55 options:0 animations:^{
//临时View(也就是截取cell大小)的frame变成和push出来view种的imageView大小一样
tempView.frame = [toVC.imageView convertRect:toVC.imageView.bounds toView:containerView];
//push控制器由透明为0变为1
toVC.view.alpha = 1;
} completion:^(BOOL finished) {
tempView.hidden = YES;
toVC.imageView.hidden = NO;
//如果动画过渡取消了就标记不完成,否则标记完成,这里可以直接写YES,如果有手势过渡才需要判断,必须标记,否则系统不会完成动画,会出现无法交互等bug
[transitionContext completeTransition:YES];
}];
}
/**
* 执行pop过渡动画
*/
- (void)doPopAnimation:(id)transitionContext
{
PEMagicMovePushController *fromVC = (PEMagicMovePushController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
PEMagicMoveController *toVC = (PEMagicMoveController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
PEMagicMoveCell *cell = (PEMagicMoveCell *)[toVC.collectionView cellForItemAtIndexPath:toVC.clickIndex];
UIView *containerView = [transitionContext containerView];
//这里的lastObject就是push适合初始化的那个tempView
UIView *tempView = containerView.subviews.lastObject;
//设置动画前状态
cell.imageV.hidden = YES; //列表页面的cell先隐藏
fromVC.imageView.hidden = YES; //当前页面的imageView也进行隐藏
tempView.hidden = NO; //最上面的临时View显示
[containerView insertSubview:toVC.view atIndex:0];
//开始pop动画
[UIView animateWithDuration:[self transitionDuration:transitionContext] delay:0.0 usingSpringWithDamping:.55 initialSpringVelocity:1/0.55 options:0 animations:^{
//将临时View的坐标和大小变成新坐标系中列表cell的坐标和大小
tempView.frame = [cell.imageV convertRect:cell.imageV.bounds toView:containerView];
//同时详情页面隐藏
fromVC.view.alpha = 0;
} completion:^(BOOL finished) {
//加入了手势判断
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
if ([transitionContext transitionWasCancelled]) {
//手势取消了,原来隐藏的imageView要显示出来
tempView.hidden = YES;
fromVC.imageView.hidden = NO;
}else{
//手势成功
cell.imageV.hidden = NO; //列表点击的cell要显示
[tempView removeFromSuperview]; //临时的要去除 因为下一次会重新生成 不会产生冗余
}
}];
}
4.现在可以在具体进行跳转的页面vc1进行使用
#pragma mark
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
//记录点击的是列表的第几个 这样在返回动画的时候能用上
_clickIndex = indexPath;
PEMagicMovePushController *vc = [[PEMagicMovePushController alloc] init];
//设置导航控制器的代理为推出的控制器,可以达到自定义不同控制器推出效果的目的
self.navigationController.delegate = vc;
[self.navigationController pushViewController:vc animated:YES];
}
5.在push出的页面vc2进行过渡动画的监听和实现
//返回手势过渡管理对象
- (id)navigationController:(UINavigationController *)navigationController animationControllerForOperation:(UINavigationControllerOperation)operation fromViewController:(UIViewController *)fromVC toViewController:(UIViewController *)toVC
{
//分pop和push两种情况分别返回动画过渡代理相应不同的动画操作
return [PENaviTransition transitionWithType:operation == UINavigationControllerOperationPush ? PENaviTransitionTypePush : PENaviTransitionTypePop];
}
//返回转场动画过渡管理对象
- (id)navigationController:(UINavigationController *)navigationController interactionControllerForAnimationController:(id)animationController
{
//如果是手动出发则返回我们的UIPercentDrivenInteractiveTransition对象
return _interactiveTransition.interation ? _interactiveTransition : nil;
}
6.完成,就是下面的效果
神奇效果.gif
DEMO TWO： 弹性present动画
1.创建两个控制器,手势管理类和DEMO ONE是同一个
2.自己具体的动画过渡实现presentAnimation和dismissAnimation两个方法
/**
* presentAnimation
*/
- (void)presentAnimation:(id)transitionContent
{
UIViewController *toVC = [transitionContent viewControllerForKey:UITransitionContextToViewControllerKey];
UIViewController *fromVC = [transitionContent viewControllerForKey:UITransitionContextFromViewControllerKey];
//snapshotViewAfterScreenUpdates:可以对某个试图截图,我们采用对这个截图做动画代替直接对toVC做动画,因为在手势过渡中直接使用toVC动画会和手势有冲突,如果不需要实现手势的话,就可以不是用截图了
UIView *tempView = [fromVC.view snapshotViewAfterScreenUpdates:NO];
tempView.frame = fromVC.view.frame;
//因为对截图做动画,fromVC开始是隐藏的
fromVC.view.hidden = YES;
//containerView:如果要对视图做转场动画,视图就必须加入containerView中才能进行,可以理解为containerView管理所有做转场动画的视图
UIView *containerView = [transitionContent containerView];
//将截图视图和toVC的view都加入containerView中 截图视图是fromVC所以先放 先放的在下面
[containerView addSubview:tempView];
[containerView addSubview:toVC.view];
//设置toVC的frame,因为是present出来不是全屏,而且在底部,如果不设置默认是整个屏幕,这里的containerView的frame就是整个屏幕
toVC.view.frame = CGRectMake(0, containerView.height, containerView.width, 500);
//开始动画,使用产生弹簧效果的方法
[UIView animateWithDuration:[self transitionDuration:transitionContent] delay:0.0 usingSpringWithDamping:0.55 initialSpringVelocity:1.0 / 0.55 options:0 animations:^{
//1.让toVC向上移动 向上是负的
toVC.view.transform = CGAffineTransformMakeTranslation(0, -500);
//2.让截图视图缩小即可
tempView.transform = CGAffineTransformMakeScale(0.85, 0.85);
} completion:^(BOOL finished) {
//使用如下代码标记整个转场过程是否正常完成[transitionContext transitionWasCancelled]代表手势是否取消了，如果取消了就传NO表示转场失败，反之亦然，如果不是用手势的话直接传YES也是可以的，我们必须标记转场的状态，系统才知道处理转场后的操作，否者认为你一直还在，会出现无法交互的情况
[transitionContent completeTransition:![transitionContent transitionWasCancelled]];
//转场失败后的处理
if ([transitionContent transitionWasCancelled])
{
//失败后复原动画开始是的样子
//1.把fromVC显示出来
fromVC.view.hidden = NO;
//2.移除截图视图,下次会重新生成
[tempView removeFromSuperview];
}
}];
}
/**
* dismissAnimation
*/
- (void)dismissAnimation:(id)transitionContent
{
UIViewController *fromVC = [transitionContent viewControllerForKey:UITransitionContextFromViewControllerKey];
UIViewController *toVC = [transitionContent viewControllerForKey:UITransitionContextToViewControllerKey];
//参照present动画的逻辑,present成功后,containerView的第一个子视图就是截图视图,我们将其取出做动画
UIView *containerView = [transitionContent containerView];
UIView *tempView = containerView.subviews[0];
//开始动画
[UIView animateWithDuration:[self transitionDuration:transitionContent] delay:0.0 usingSpringWithDamping:0.55 initialSpringVelocity:1 / 0.55 options:0 animations:^{
//present使用的是transform,只需要恢复就可以了
fromVC.view.transform = CGAffineTransformIdentity;
tempView.transform = CGAffineTransformIdentity;
} completion:^(BOOL finished) {
if ([transitionContent transitionWasCancelled]) {
//标记失败
[transitionContent completeTransition:NO];
}else{
//成功后,标记成功,让toVC显示出来,并移除截图视图
[transitionContent completeTransition:YES];
toVC.view.hidden = NO;
[tempView removeFromSuperview];
}
}];
}
3.vc1中进行调用
PEElasticOneController *elasticVC = [PEElasticOneController new];
elasticVC.delegate = self;
[self presentViewController:elasticVC animated:YES completion:nil];
4.vc2中监听
#pragma mark - ---UIViewControllerTransitioningDelegate---
- (id)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source
{
return [PEElasticTransition transitionWithTransitionType:PEElasticTransitionTypePresent];
}
- (id)animationControllerForDismissedController:(UIViewController *)dismissed
{
return [PEElasticTransition transitionWithTransitionType:PEElasticTransitionTypeDismiss];
}
- (id)interactionControllerForPresentation:(id)animator
{
PEInteractiveTransition *interactivePresent = [self.delegate interactiveTransitionForPresent];
return interactivePresent.interation ? interactivePresent : nil;
}
- (id)interactionControllerForDismissal:(id)animator
{
return self.interactiveTransition.interation ? self.interactiveTransition : nil;
}
这样就基本完成了
弹性present.gif
DEMO THREE:翻页push效果
1.其它和上面的相似,直接来看核心的过渡动画实现:
/**
* 自定义push动画
*/
- (void)doPushAnimation:(id)transitionContext
{
UIViewController *fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
//对当前view截图 然后作为动画对象
UIView *tempV = [fromVC.view snapshotViewAfterScreenUpdates:NO];
tempV.frame = fromVC.view.frame;
UIView *containerV = [transitionContext containerView];
//临时的放最上面 做过渡
[containerV addSubview:toVC.view];
[containerV addSubview:tempV];
fromVC.view.hidden = YES;
//设置anchorPoint 选择的支点
[tempV setAnchorPoint:CGPointMake(0, 0.5)];
CATransform3D transform3d = CATransform3DIdentity;
//m34（透视效果，要操作的这个对象要有旋转的角度，否则没有效果。正直/负值都有意义）;
transform3d.m34 = -0.002;
containerV.layer.sublayerTransform = transform3d;
//增加阴影
CAGradientLayer *fromGradient = [CAGradientLayer layer];
fromGradient.frame = fromVC.view.bounds;
fromGradient.colors = @[(id)[UIColor blackColor].CGColor,(id)[UIColor blackColor].CGColor];
fromGradient.startPoint = CGPointMake(0.0, 0.5);
fromGradient.endPoint = CGPointMake(0.8, 0.5);
UIView *fromShadow = [[UIView alloc] initWithFrame:fromVC.view.bounds];
fromShadow.backgroundColor = [UIColor clearColor];
[fromShadow.layer insertSublayer:fromGradient atIndex:1];
fromShadow.alpha = 0.0;
[tempV addSubview:fromShadow];
CAGradientLayer *toGradient = [CAGradientLayer layer];
toGradient.frame = fromVC.view.bounds;
toGradient.colors = @[(id)[UIColor blackColor].CGColor,(id)[UIColor blackColor].CGColor];
toGradient.startPoint = CGPointMake(0.0, 0.5);
toGradient.endPoint = CGPointMake(0.8, 0.5);
UIView *toShadow = [[UIView alloc] initWithFrame:fromVC.view.bounds];
toShadow.backgroundColor = [UIColor clearColor];
[toShadow.layer insertSublayer:toGradient atIndex:1];
toShadow.alpha = 1.0;
[toVC.view addSubview:toShadow];
//开始动画
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
//沿Y轴旋转 逆时针180°
tempV.layer.transform = CATransform3DMakeRotation(-M_PI_2, 0, 1, 0);
//当前的由亮变暗 push的VC由暗变亮
fromShadow.alpha = 1.0;
toShadow.alpha = 0.0;
} completion:^(BOOL finished) {
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
//动画取消的操作
if ([transitionContext transitionWasCancelled]){
[tempV removeFromSuperview];
fromVC.view.hidden = NO;
}
}];
}
/**
* 自定义pop动画
*/
- (void)doPopAnimation:(id)transitionContext
{
UIViewController *fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIView *containerV = [transitionContext containerView];
UIView *tempV = containerV.subviews.lastObject;
[containerV addSubview:toVC.view];
//开始动画
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
//临时图层恢复原状
tempV.layer.transform = CATransform3DIdentity;
fromVC.view.subviews.lastObject.alpha = 1.0;
tempV.subviews.lastObject.alpha = 0.0;
} completion:^(BOOL finished) {
if ([transitionContext transitionWasCancelled]){
[transitionContext completeTransition:NO];
}else{
[transitionContext completeTransition:YES];
[tempV removeFromSuperview];
toVC.view.hidden = NO;
}
}];
}
2.手势加上的效果如下:
![Uploading 翻页效果_161246.gif . . .]
DEMO FOUR:圆点扩散present效果
1.其它和上面相似,来看核心过渡的动画实现
- (void)presentAnimation:(id)transitionContext
{
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UINavigationController *fromVC = (UINavigationController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UIView *containerV = [transitionContext containerView];
PECircleSpreadController *temp = fromVC.viewControllers.lastObject;
[containerV addSubview:toVC.view];
//画两个圆路径
UIBezierPath *startCircle = [UIBezierPath bezierPathWithOvalInRect:temp.buttonFrame];
//始终用最大的x值和y值的平方根 来作为圆的半径 这样保证了圆点中心到最远的边的距离作为半径
CGFloat x = MAX(temp.buttonFrame.origin.x, containerV.frame.size.width - temp.buttonFrame.origin.x);
CGFloat y = MAX(temp.buttonFrame.origin.y, containerV.frame.size.height - temp.buttonFrame.origin.y);
CGFloat radius = sqrtf(pow(x, 2) + pow(y, 2));
//圆心 半径 开始角度 结束角度M_PI*2是360° 是否顺时针
UIBezierPath *endCircle = [UIBezierPath bezierPathWithArcCenter:containerV.center radius:radius startAngle:0 endAngle:M_PI * 2 clockwise:YES];
//创建CAShapLayer进行遮盖
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.path = endCircle.CGPath;
//将maskLayer作为toVC的遮盖
toVC.view.layer.mask = maskLayer;
//创建路径动画
CABasicAnimation *maskLayerAnimation = [CABasicAnimation animationWithKeyPath:@"path"];
//动画是添加到layer上的,所以必须为CGPath,再将CGPath桥接为OC对象
maskLayerAnimation.fromValue = (__bridge id)(startCircle.CGPath);
maskLayerAnimation.toValue = (__bridge id)(endCircle.CGPath);
maskLayerAnimation.duration = [self transitionDuration:transitionContext];
maskLayerAnimation.delegate = self;
maskLayerAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; //动画速度: 先慢 后慢 中间快
[maskLayerAnimation setValue:transitionContext forKey:@"transitionContext"];
[maskLayer addAnimation:maskLayerAnimation forKey:@"path"];
}
- (void)dismissAnimation:(id)transitionContext
{
PECircleSpreadPresentedController *fromVC = (PECircleSpreadPresentedController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UINavigationController *toVC = (UINavigationController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
PECircleSpreadController *temp = toVC.viewControllers.lastObject;
UIView *containerV = [transitionContext containerView];
//画两个圆的路径
CGFloat radius = sqrtf(pow(containerV.frame.size.height, 2) + pow(containerV.frame.size.width, 2))/2.0;
UIBezierPath *startCircle = [UIBezierPath bezierPathWithArcCenter:containerV.center radius:radius startAngle:0 endAngle:M_PI*2 clockwise:YES];
temp.buttonFrame = fromVC.presentButtonFrame;
UIBezierPath *endCircle = [UIBezierPath bezierPathWithOvalInRect:temp.buttonFrame];
//创建CAShapeLayer进行覆盖
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.fillColor = [UIColor greenColor].CGColor;
maskLayer.path = endCircle.CGPath;
fromVC.view.layer.mask = maskLayer;
//创建路径动画
CABasicAnimation *maskLayerAnimation = [CABasicAnimation animationWithKeyPath:@"path"];
maskLayerAnimation.delegate = self;
maskLayerAnimation.fromValue = (__bridge id)(startCircle.CGPath);
maskLayerAnimation.toValue = (__bridge id)(endCircle.CGPath);
maskLayerAnimation.duration = [self transitionDuration:transitionContext];
maskLayerAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
[maskLayerAnimation setValue:transitionContext forKey:@"transitionContext"];
[maskLayer addAnimation:maskLayerAnimation forKey:@"path"];
}
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag
{
switch (_type) {
case PECircleSpreadTransitionTypePresent:{
id transitionContext = [anim valueForKey:@"transitionContext"];
[transitionContext completeTransition:YES];
}
break;
case PECircleSpreadTransitionTypeDismiss:{
id transitionContext = [anim valueForKey:@"transitionContext"];
[transitionContext completeTransition:![transitionContext transitionWasCancelled]];
if ([transitionContext transitionWasCancelled]) {
//去掉遮挡层
[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey].view.layer.mask = nil;
}
}
break;
default:
break;
}
}
注意:最后animationDidStop的代理方法中处理到动画的完成逻辑.
2.最后的效果如下:
小圆点扩散.gif
总结
1、关于：self.modalPresentationStyle = UIModalPresentationCustom;我查看了视图层级后发现，如果使用了Custom，在present动画完成的时候，presentingView也就是demo one中的vc1的view会从containerView中移除，只是移除，并未销毁，此时还被持有着(dismiss后还得回来呢！)，如果设置custom，那么present完成后，它一直都在containerView中，只是在最后面，所以需不需要设置custom可以看动画完成后的情况，是否还需要看见presentingViewController，但是记住如果没有设置custom，在disMiss的动画逻辑中，要把它加回containerView中，不然就不在咯~！
2、感觉写了好多东西，其实只要弄懂了转场的逻辑，其实就只需要写动画的逻辑就行了，其他东西都是固定的，而且苹果提供的这种控制转场的方式可充分解耦，除了写的手势过渡管理可以拿到任何地方使用，所有的动画过渡管理者都可以很轻松的复用到其他转场中，都不用分是何种转场，demo没有写标签控制器的转场，实现方法也是完全类似的，大家可以尝试一下，四个demo的github地址： 自定义转场动画demo