随机颜色

 //随机颜色

    intR = (arc4random() % 256) ;

    intG = (arc4random() % 256) ;

    intB = (arc4random() % 256) ;

   self.colorView.layer.borderColor =[UIColor colorWithRed:R/255.0 green:G/255.0 blue:B/255.0 alpha:1].CGColor;