向外扩散的圆形动画

-(void)addanimationwithView:(UIView *)circleView{    

NSInteger pulsingCount = 5;    

double animationDuration = 5;    

CALayer *animationLayer = [CALayer layer];   

 for (int i = 0; i < pulsingCount; i++) {        

CALayer * pulsingLayer = [CALayer layer];//        

pulsingLayer.frame = CGRectMake(0, 0, circleView.frame.size.width, circleView.frame.size.height);       

 pulsingLayer.frame = CGRectMake(0, 0, YC_directionX(300), YC_directionX(300));//        

pulsingLayer.frame = circleView.bounds;//        

pulsingLayer.borderColor = NavColor.CGColor;        pulsingLayer.borderColor = [UIColor colorWithHexString:@"#CFEECF"].CGColor;        

pulsingLayer.borderWidth = 15;//      

  pulsingLayer.cornerRadius = circleView.frame.size.width / 2;        

pulsingLayer.cornerRadius = YC_directionX(150);                

CAMediaTimingFunction * defaultCurve = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];                

CAAnimationGroup * animationGroup = [CAAnimationGroup animation];        

animationGroup.fillMode = kCAFillModeBackwards;        

animationGroup.beginTime = CACurrentMediaTime() + (double)i * animationDuration / (double)pulsingCount;        

animationGroup.duration = animationDuration;        

animationGroup.repeatCount = HUGE;        

animationGroup.timingFunction = defaultCurve;        

animationGroup.removedOnCompletion = false;                

CABasicAnimation * scaleAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];        

scaleAnimation.fromValue = @1.0;        

scaleAnimation.toValue = @2.2;                

CAKeyframeAnimation * opacityAnimation = [CAKeyframeAnimation animationWithKeyPath:@"opacity"];        

opacityAnimation.values = @[@1, @0.9, @0.8, @0.7, @0.6, @0.5, @0.4, @0.3, @0.2, @0.1, @0];        

opacityAnimation.keyTimes = @[@0, @0.1, @0.2, @0.3, @0.4, @0.5, @0.6, @0.7, @0.8, @0.9, @1];                

animationGroup.animations = @[scaleAnimation, opacityAnimation];  

 [pulsingLayer addAnimation:animationGroup forKey:@"plulsing"];        

[animationLayer addSublayer:pulsingLayer];    

}    

[circleView.layer addSublayer:animationLayer];

}