最近模仿潮汐,发现不会实现自定义转场动画,就学习了下,还是有点不是很清晰,写下感想反思
View Controller Transition(控制器过渡)
每个 View Controller 是一个 Scene，View Controller Transition 便是从一个 Scene 转换到另外一个 Scene.
model转场方式仅限于modalPresentationStyle属性为 UIModalPresentationFullScreen 或 UIModalPresentationCustom 这两种模式
如果是试图控制器A跳转至B
自定义跳转需要三个东西:
1.转场代理
A作为代理,遵守UIViewControllerTransitioningDelegate协议
2.动画控制器(Animation Controller)：
负责添加视图以及执行动画. 可创建两个遵守UIViewControllerAnimatedTransitioning的对象C,D,实现A到B和B到A的动画效果
3.转场环境
由UIKit提供
对象A实现UIViewControllerTransitioningDelegate 的两个方法:
- (id<UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController*)presented presentingController:(UIViewController*)presenting sourceController ///返回对象C
-(id<UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController*)dismissed //返回对象D
对象C.D实现UIViewControllerAnimatedTransitioning 协议的两个方法:
- (NSTimeInterval)transitionDuration:(id<UIViewControllerAnimatedTransitioning>)transitionContext
返回动画执行时间
- (void)animateTransition:(id<UIViewControllerAnimatedTransitioning>)transitionContext
从A到B,或者从B到A的动画效果
例:对象C中主要代码(负责A到B):
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext
{
// 1. Get controllers from transition context
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
// 2. Set init frame for toVC
CGRect screenBounds = [[UIScreen mainScreen] bounds];
CGRect finalFrame = [transitionContext finalFrameForViewController:toVC];
toVC.view.frame = CGRectOffset(finalFrame, 0, screenBounds.size.height);
// 3. Add toVC's view to containerView
UIView *containerView = [transitionContext containerView];
[containerView addSubview:toVC.view];
// 4. Do animate now
NSTimeInterval duration = [self transitionDuration:transitionContext];
[UIView animateWithDuration:duration
delay:0.0
usingSpringWithDamping:0.6
initialSpringVelocity:0.0
options:UIViewAnimationOptionCurveLinear
animations:^{
toVC.view.frame = finalFrame;
} completion:^(BOOL finished) {
// 5. Tell context that we completed.
[transitionContext completeTransition:YES];
}];
}
这是我学习的demo:https://github.com/onevcat/VCTransitionDemo
更详细的可参见http://blog.devtang.com/2016/03/13/iOS-transition-guide/
