脉冲层
向任何任意UIView添加可自定义的CALayer光晕效果。
完全用Swift编写。
如何使用
haloLayer = PulsingLayer ( pulseColor : UIColor ( white : 1.0 , alpha : 1.0 ))
haloLayer. radius = 90.0
haloLayer. animationDuration = 1
haloLayer. pulseInterval = 0
haloView = UIView ( frame : CGRectMake ( 65 , 65 , 50 , 50 ));
haloLayer. position = CGPointMake ( CGRectGetWidth (haloView. frame ) / 2 , CGRectGetHeight (haloView. frame