由于某种原因，当我从移动设备访问我的应用程序时，导航栏消失了。调整大小时在桌面上可以正常工作，但不能在手机上工作。有人知道为什么吗？
导航栏组件：
<div class="nav-wrapper">
<div class="container nav-container">
<nav class="navbar navbar-expand-md">
<button class="navbar-icon justify-content-start" type="button" data-toggle="collapse" data-target="#collapsingNavbar">
<svg width="45" height="45" xmlns="http://www.w3.org/2000/svg">
<g>
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</g>
</svg>
<small class="text-white nav-icon-text">Meny</small>
</button>
<div class="navbar-collapse collapse justify-content-end" id="collapsingNavbar">
<ul class="navbar-nav">
<li class="nav-item">
<a class="nav-link text-white" routerLink="/home">Hem</a>
</li>
<li class="nav-item">
<a class="nav-link text-white" id="login" routerLink="{{loginRout}}">{{loginStateText}}</a>
</li>
</ul>
</div>
</nav>
</div>
</div>
答案 0 :(得分：0)
我认为它并没有消失。由于类navbar-collapse合拢，它在断点处合拢。从Bootstrap文档中，这两个类用于-
.collapse.navbar-collapse用于将导航栏内容分组和隐藏 父断点。