修改navigationController的背景色和隐藏navigationController下黑线

一.修改背景色
self.navigationController.navigationBar.barTintColor =[UIColor colorWithRed:0.980 green:0.979 blue:0.000 alpha:1.000];
二.隐藏黑线
- (void)viewDidLoad {
[super viewDidLoad];
[self findHairlineImageViewUnder:self.navigationController.navigationBar].hidden = YES;
}

• (UIImageView * )findHairlineImageViewUnder:(UIView * )view {

  if ([view isKindOfClass:UIImageView.class] && view.bounds.size.height <= 1.0) {

  return (UIImageView *)view;
  

  }

  for (UIView *subview in view.subviews) {

  UIImageView *imageView = [self findHairlineImageViewUnder:subview];
  
  if (imageView) {
  
      return imageView;
  }
  

  }

  return nil;
  }