A（AViewController）通过Present方式转场到B（BViewController）
- 通知系统使用自定义转场而不是默认转场
// AViewController.m
- (IBAction)handleNextButtonPressed:(id)sender {
BViewController *bVC = [BViewController new];
bVC.transitioningDelegate = self;
bVC.modalPresentationStyle = UIModalPresentationCustom;// present之后不会移除AViewController.view，因此dismiss动画对象中不用添加toView了
[self presentViewController:bVC animated:YES completion:^{
}];
}
// AViewController.m
// 实现UIViewControllerTransitioningDelegate协议中的方法
- (id<UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source {
return _presentAnimation; //_presentAnimatino为实现了UIViewControllerAnimatedTransitioning协议的动画对象
}
- 实现具体动画效果
// PresentAnimation.m
@implementation PresentAnimation
- (NSTimeInterval)transitionDuration:(id<UIViewControllerContextTransitioning>)transitionContext {
return 0.6;
}
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext {
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
UIView *containerView = [transitionContext containerView];
[containerView addSubview:toVC.view];
CGRect targetFrame = [transitionContext finalFrameForViewController:toVC];
toVC.view.frame = CGRectOffset(targetFrame, CGRectGetWidth(targetFrame), -CGRectGetHeight(targetFrame));
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
toVC.view.frame = targetFrame;
} completion:^(BOOL finished) {
[transitionContext completeTransition:YES];
}];
}
@end
B（BViewController）通过dismiss方式转场到A（AViewController）
- 通知系统使用自定义转场而不是默认转场
// BViewController.m
- (IBAction)handeBackButtonPressed:(id)sender {
self.transitioningDelegate = self;// 抢回Delegate
[self dismissViewControllerAnimated:YES completion:^{
}];
}
// BViewController.m
// 实现UIViewControllerTransitioningDelegate协议中的方法
- (nullable id <UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed {
return _dismissAnimation;
}
- 实现具体动画效果
// DismissAnimation.m
@implementation DismissAnimation
- (NSTimeInterval)transitionDuration:(id<UIViewControllerContextTransitioning>)transitionContext {
return 0.6;
}
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext {
UIViewController *fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
CGRect targetFrame = [transitionContext initialFrameForViewController:fromVC];
targetFrame = CGRectOffset(targetFrame, CGRectGetWidth(targetFrame), - CGRectGetHeight(targetFrame));
[UIView animateWithDuration:[self transitionDuration:transitionContext] animations:^{
fromVC.view.frame = targetFrame;
} completion:^(BOOL finished) {
[transitionContext completeTransition:YES];
}];
}
@end
