将类从navbar-light更改为navbar-dark会隐藏navbar

Question

我正在建立一个网站使用Laravel和Bootstrap CSS框架。我在页面的顶部有一个导航栏，用于在不同的页面之间导航。默认情况下，Laravel将导航栏类设置为navbar-light。因为我不希望导航栏是白色的，所以我把它改成了navbar-dark。当我这样做时，导航栏中的所有内容都消失了，只剩下没有任何内容的白条。我做错了什么？

<nav class="navbar navbar-expand-md navbar-dark navbar-laravel" style="margin-bottom: 20px;">
    <div class="container">
        <a class="navbar-brand" href="{{ url('/') }}">
        {{ config('app.name', 'Laravel') }}
        </a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
        </button>
        <div class="collapse navbar-collapse" id="navbarSupportedContent">
            <!-- Left Side Of Navbar -->
            <ul class="navbar-nav mr-auto">
                <li class="nav-item">
                    <a class="nav-link" href="/">Home <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">Messages <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">People <span class="sr-only">(current)</span></a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#">Photos <span class="sr-only">(current)</span></a>
                </li>
            </ul>
            <!-- Right Side Of Navbar -->
            <ul class="navbar-nav ml-auto">
                <!-- Authentication Links -->
                @guest
                <li><a class="nav-link" href="{{ route('login') }}">Login</a></li>
                <li><a class="nav-link" href="{{ route('register') }}">Register</a></li>
                @else
                <li class="nav-item dropdown">
                    <a class="nav-link dropdown-toggle" href="#" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                    {{ Auth::user()->name }} <span class="caret"></span>
                    </a>
                    <div class="dropdown-menu" aria-labelledby="navbarDropdown">
                        <a class="dropdown-item" href="dashboard">
                        Dashboard
                        </a>
                        <a class="dropdown-item" href="{{ route('logout') }}"
                            onclick="event.preventDefault();
                            document.getElementById('logout-form').submit();">
                        Logout
                        </a>
                        <form id="logout-form" action="{{ route('logout') }}" method="POST" style="display: none;">
                            @csrf
                        </form>
                    </div>
                </li>
                @endguest
            </ul>
        </div>
    </div>
</nav>

Answer 1

您还需要在navbar-dark中额外添加类bg-dark。

navbar-dark基本上只是确定文本应该是什么颜色，即深色导航栏的浅色文本和浅色导航栏的深色文本。

然后，bg-dark确定导航栏的实际背景颜色。但其他颜色也同样适用。例如，bg-primary或bg-danger可以很好地与navbar-dark配合使用。

Answer 2

添加bg-dark类

<nav class="navbar navbar-expand-md navbar-dark bg-dark navbar-laravel">