iOS 去掉导航栏下面黑线 —— HERO博客

去掉导航栏self.navigationController.navigationBar下默认黑线。

方法一：（会影响导航栏的translucent透明属性）

//视图将要显示时隐藏
-(void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    
    [self.navigationController.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
    [self.navigationController.navigationBar setShadowImage:[UIImage new]];
}

//视图将要消失时取消隐藏
-(void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    
    [self.navigationController.navigationBar setBackgroundImage:nil forBarMetrics:UIBarMetricsDefault];
    [self.navigationController.navigationBar setShadowImage:nil];
}

方法二：

@property (nonatomic, weak) UIImageView *lineView;

//视图加载完成获取到导航栏最下面的黑线
- (void)viewDidLoad {
    [super viewDidLoad];
    
    //获取导航栏下面黑线
    _lineView = [self getLineViewInNavigationBar:self.navigationController.navigationBar];
}

//视图将要显示时隐藏
- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    
    _lineView.hidden = YES;
    self.navigationController.navigationBar.translucent = YES;
    self.navigationController.navigationBar.barTintColor = [UIColor whiteColor];
}

//视图将要消失时取消隐藏
- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    
    _lineView.hidden = NO;
    self.navigationController.navigationBar.translucent = NO;
    self.navigationController.navigationBar.barTintColor = [UIColor blackColor];
}

//找到导航栏最下面黑线视图
- (UIImageView *)getLineViewInNavigationBar:(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 getLineViewInNavigationBar:subview];
        if (imageView) {
            return imageView;
        }
    }
    
    return nil;
}