func createRadarView(){
        UIView.animateWithDuration(0, delay: 3, options: UIViewAnimationOptions.Repeat, animations: { () -> Void in
            self.rotationView.transform = CGAffineTransformMakeRotation(M_PI_4)
        }) { (Bool) -> Void in
            
        }
    }

这么写总报上图的错误，不知道什么原因