闪烁动画

#import <QuartzCore/QuartzCore.h>

@interface CABasicAnimation (Category)
/**
 *  forever twinkling  永久闪烁的动画
 *
 *  @param time   time duration 持续时间
 *
 *  @return self   返回当前类
 */
+ (CABasicAnimation *)opacityForever_Animation:(float)time;

@end

//===========================================华丽的分割线===============================================

#import "CABasicAnimation+Category.h"

@implementation CABasicAnimation (Category)

#pragma mark === 永久闪烁的动画 ======
+ (CABasicAnimation *)opacityForever_Animation:(float)time {
    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"opacity"];//必须写opacity才行。
    animation.fromValue = @1.f;
    animation.toValue = @0;//这是透明度。
    animation.autoreverses = YES; //
    animation.duration = time;
    animation.repeatCount = MAXFLOAT;
    animation.removedOnCompletion = NO;
    animation.fillMode = kCAFillModeForwards;
    //定义动画的样式 渐入式   timingFunction 控制动画运行的节奏
    animation.timingFunction =[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
    return animation;
}

@end