navgationBar底部线条问题

隐藏线条
https://blog.csdn.net/li_yangyang_li/article/details/51272033?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-2.nonecase&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-2.nonecase

改变线条颜色

//设置导航栏底部线条颜色
   UINavigationBar *navigationBar = self.navigationBar;
//    [navigationBar setBackgroundImage:[[UIImage alloc] init] forBarPosition:UIBarPositionAny barMetrics:UIBarMetricsDefault]; //此处使底部线条颜色为浅灰色
   CGRect rect = CGRectMake(0, 0, SCREEN_WIDTH, 1);
   UIGraphicsBeginImageContext(rect.size);
   CGContextRef context = UIGraphicsGetCurrentContext();
   UIColor *color = rgba(238, 238, 238, 1);
   CGContextSetFillColorWithColor(context, [color CGColor]);
   CGContextFillRect(context, rect);
   UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
   UIGraphicsEndImageContext();
   [navigationBar setShadowImage:img];