iOS 隐藏导航栏下分割线

方法1:直接隐藏: 

// 在页面出现的时候就将黑线隐藏起来
- (void)viewWillAppear:(BOOL)animated {
     [self.navigationController.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
     [self.navigationController.navigationBar setShadowImage:[UIImage new]];
}

// 在页面消失的时候就让navigationbar还原样式
- (void)viewWillDisappear:(BOOL)animated{
    [self.navigationController.navigationBar setBackgroundImage:nil forBarMetrics:UIBarMetricsDefault];
    [self.navigationController.navigationBar setShadowImage:nil];
}

这个方法唯一的不好就是会影响导航栏的translucent(透明)属性

 

方法2:找出黑线,再做处理:

// 找到这个黑线
- (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;
}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    _navBarHairlineImageView.hidden = YES;
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    _navBarHairlineImageView.hidden = NO;
}