用过格瓦拉电影，或者其他app可能都知道，一种点击按钮用放大效果实现转场的动画现在很流行，效果大致如下
自定义转场动画
首先就要声明一个遵守UIViewControllerAnimatedTransitioning协议的类.
然后实现协议中的两个函数
// This is used for percent driven interactive transitions, as well as for container controllers that have companion animations that might need to
// 返回转场时间
- (NSTimeInterval)transitionDuration:(nullable id <UIViewControllerContextTransitioning>)transitionContext;
// 转场的动作
- (void)animateTransition:(id <UIViewControllerContextTransitioning>)transitionContext;
push和pop都在animateTransition:里面实现，所以需要一个参数表示是push还是pop；还有一个参数表示转场时间
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
typedef enum : NSUInteger {
animate_push = 0,
animate_pop = 1,
} Animate_Type;
@interface SFTrainsitionAnimate : NSObject<UIViewControllerAnimatedTransitioning>
- (instancetype)initWithAnimateType:(Animate_Type)type andDuration:(CGFloat)dura;
@property (assign, nonatomic) CGFloat duration;
@property (assign, nonatomic) Animate_Type type;
@end
那么要如何使用新建的对象呢？可以通过UINavigationControllerDelegate中的
- (id<UIViewControllerAnimatedTransitioning>)navigationController:(UINavigationController *)navigationController animationControllerForOperation:(UINavigationControllerOperation)operation fromViewController:(UIViewController *)fromVC toViewController:(UIViewController *)toVC{
if (operation == UINavigationControllerOperationPush) {
self.animate = [[SFTrainsitionAnimate alloc] init];
return self.animate;
}else{
return nil;
}
}
当然，要调用这个方法还得先把UINavigationControllerDelegate委托给视图控制器
self.navigationController.delegate = self;
再来看看UIViewControllerAnimatedTransitioning这个协议，返回时间的方法就不介绍了。重点在
- (void)animateTransition:(id<UIViewControllerContextTransitioning>)transitionContext{
//起始视图控制器
UIViewController *fromVC = [transitionContext viewControllerForKey:UITransitionContextFromViewControllerKey];
//目标视图控制器
UIViewController *toVC = [transitionContext viewControllerForKey:UITransitionContextToViewControllerKey];
//在这个视图上实现跳转动画
UIView *containView = [transitionContext containerView];
}
如上注释，我们可以通过参数
