iOS 导航条背景透明

1.创建一个全局变量_navBackView

@interface ViewController ()

{

    UIView *_navBackView;

}

@end

2.将getBackView:方法复制粘贴到代码中

-(void)getBackView:(UIView*)superView

{

    if ([superView isKindOfClass:NSClassFromString(@"_UINavigationBarBackground")])

    {

        //移除分割线

        for (UIView *view in superView.subviews)

        {

            if ([view isKindOfClass:[UIImageView class]])

            {

                [view removeFromSuperview];

            }

        }

        _navBackView = superView;

        _navBackView.backgroundColor = [UIColor yellowColor];

        _navBackView.alpha = 0;

    }

    else if ([superView isKindOfClass:NSClassFromString(@"_UIBackdropView")])

    {

        //_UIBackdropEffectView是_UIBackdropView的子视图，这是只需隐藏父视图即可

        superView.hidden = YES;

    }

    

    for (UIView *view in superView.subviews)

    {

        [self getBackView:view];

    }

}

3.在页面即将出现时调用此方法，传入参数为self.navigationController.navigationBar

-(void)viewDidAppear:(BOOL)animated

{

[self getBackView:self.navigationController.navigationBar];

}