iOS开发iOS13以后修改导航栏的背景颜色和导航栏底部的线

    NSDictionary *titleTextAttributes = @{NSFontAttributeName:LYBoldFont(17), NSForegroundColorAttributeName:[UIColor whiteColor]};
    
    ///控制导航栏的背景颜色和底部线的隐藏
    if (@available(iOS 13.0, *)) {
        UINavigationBarAppearance *appearance = [UINavigationBarAppearance new];
        [appearance configureWithOpaqueBackground];//重置导航栏背景颜色和阴影
        appearance.backgroundColor = [UIColor clearColor];
        appearance.shadowImage = [UIImage new];
        appearance.shadowColor = nil;
        appearance.titleTextAttributes = titleTextAttributes;
        self.navigationBar.standardAppearance = appearance;
        self.navigationBar.scrollEdgeAppearance = appearance;
    } else {
        // Fallback on earlier versions
        self.navigationBar.barTintColor = [UIColor clearColor];
        [self.navigationBar setTitleTextAttributes:titleTextAttributes];
        [self.navigationBar setShadowImage:[UIImage new]];
        [self.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];

    }