iOS 自定义转场动画
iOS内部提供了自定义转场动画的代理
@property (nullable, nonatomic, weak) id <UIViewControllerTransitioningDelegate> transitioningDelegate;
我们可以在UIViewController直接写转场动画，也可以新建一个类写转场动画，首先我们要给要跳转的UIViewController设置transitioningDelegate
- (instancetype)init {
self = [super init];
if (self) {
self.transitioningDelegate = self;
}
return self;
}
然后实现几个代理方法
- (nullable id <UIViewControllerAnimatedTransitioning>)animationControllerForPresentedController:(UIViewController *)presented presentingController:(UIViewController *)presenting sourceController:(UIViewController *)source {
return self;
}
- (nullable id <UIViewControllerAnimatedTransitioning>)animationControllerForDismissedController:(UIViewController *)dismissed {
return self;
}
- (NSTimeInterval)transitionDuration:(nullable id <UIViewControllerContextTransitioning>)transitionContext {
return 0.3;//这里设置动画时长
}
//所有的过渡动画事务都在这个方法里面完成
- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext{
//取出转场前后的视图控制器
UIViewController * fromVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
UIViewController * toVC = (UIViewController *)[transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
//取出转场前后视图控制器上的视图view
UIView* toView = [transitionContext viewForKey:UITransitionContextToViewKey]?:toVC.view;
UIView* fromView = [transitionContext viewForKey:UITransitionContextFromViewKey]?:fromVC.view;
//这里有个重要的概念containerView，containerView作为要present的view的控制view，要present的view的所有动画都是在containerView上执行的，这里模仿一个类似京东的加入购物车弹出选择规格动画
UIView*containerView = [transitionContext containerView];
//这里判断toView是否是要present的view，如果是，那么是在做present动画，如果不是，那么是在执行dismiss动画
//这里要特别说明，动画执行完成时，要调用 [transitionContext completeTransition:YES];这是在通知系统动画完成了，如果没有这一句，那么相当于转场动画没执行完成，导致页面无法点击，如果在执行了这一句代码时，，，继续对页面进行动画，会导致动画失效
if(toView == self.view) {
toView.frame = containerView.bounds;
[containerView addSubview:toView];
CATransform3D transform = CATransform3DIdentity;
transform.m34 = -1/1000;
transform = CATransform3DRotate(transform,M_PI/16,1,0,0);
transform = CATransform3DTranslate(transform,0,0, -100);
transform = CATransform3DScale(transform,0.96,0.96,1);
[UIView animateWithDuration:0.5 animations:^{
fromView.layer.transform= transform;
}completion:^(BOOLfinished) {
[transitionContext completeTransition:YES];
}];
}else{
[UIView animateWithDuration:0.3 animations:^{
toView.layer.transform = CATransform3DMakeScale(1, 1, 1);
} completion:^(BOOL finished) {
[fromView removeFromSuperview];
[transitionContext completeTransition:YES];
}];
}
}
