image.png

#import <QuartzCore/CoreAnimation.h>
@protocol YLBAnimationWeakDelegate <NSObject>
@optional
- (void)animationDidStart:(CAAnimation *)anim;
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag;
@end

@interface YLBAnimationDelegateManager : NSObject <CAAnimationDelegate>
@property (weak, nonatomic) id<YLBAnimationWeakDelegate> delegate;
@end

@implementation YLBAnimationDelegateManager
- (void)animationDidStart:(CAAnimation *)anim {
    if (_delegate && [_delegate respondsToSelector:@selector(animationDidStart:)]) {
        [_delegate animationDidStart:anim];
    }
}
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {
    if (_delegate && [_delegate respondsToSelector:@selector(animationDidStop:finished:)]) {
        [_delegate animationDidStop:anim finished:flag];
    }
}
@end

使用方法：

CAKeyframeAnimation *moveAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"];
YLBAnimationDelegateManager * manager = [YLBAnimationDelegateManager new]; //創(chuàng)建實(shí)例
manager.delegate = self; //進(jìn)行弱引用
moveAnimation.delegate = manager; //進(jìn)行強(qiáng)引用