//IOS 隐藏导航栏下面黑色分割线

//简单记录一下
//IOS 隐藏导航栏下面黑色分割线
第一步

 [self.navigationController.navigationBar setShadowImage:[UIImage imageWithColor:[UIColor clearColor]]];

这里的imageWithColor 是对UIImage的分类
附上代码段

+ (UIImage *)imageWithColor:(UIColor *)color {

    CGRect rect = CGRectMake(0, 0, 1, 1);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}