使用 ng-bootstrap (4) angular 2 (cli) 的导航栏中的下拉切换问题

Question

我按照here 中的说明进行操作，css 运行良好。对于下拉切换，我使用了此代码

<nav class="navbar navbar-light bg-faded">
  <a class="navbar-brand" href="#">Navbar</a>
  <ul class="nav navbar-nav">
    <li class="nav-item active">
      <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Link</a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Link</a>
    </li>
    <li class="nav-item dropdown">
      <a class="nav-link dropdown-toggle" href="#" id="supportedContentDropdown" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown</a>
      <div class="dropdown-menu" aria-labelledby="supportedContentDropdown">
        <a class="dropdown-item" href="#">Action</a>
        <a class="dropdown-item" href="#">Another action</a>
        <a class="dropdown-item" href="#">Something else here</a>
      </div>
    </li>
  </ul>
  <form class="form-inline float-xs-right">
    <input class="form-control" type="text" placeholder="Search">
    <button class="btn btn-outline-success" type="submit">Search</button>
  </form>
</nav>

但下拉切换不起作用，尽管我为 Root 包含了 NgbModule。请告诉我是否必须在组件提供程序数组或其他任何内容中包含其他内容。 提前致谢

Answer 1

我是这样工作的：

<nav class="navbar navbar-light bg-faded">
  <a class="navbar-brand" href="#">Navbar</a>
  <ul class="nav navbar-nav">
    <li class="nav-item active">
      <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Link</a>
    </li>
    <li class="nav-item">
      <a class="nav-link" href="#">Link</a>
    </li>
    <li class="nav-item dropdown">
      <div ngbDropdown class="d-inline-block">
        <button class="btn btn-outline-primary" id="dropdownMenu1" ngbDropdownToggle>Toggle dropdown</button>
        <div ngbDropdownMenu class="dropdown-menu" aria-labelledby="dropdownMenu1">
          <button class="dropdown-item">Action - 1</button>
          <button class="dropdown-item">Another Action</button>
          <button class="dropdown-item">Something else is here</button>
        </div>
      </div>
    </li>
  </ul>
  <form class="form-inline float-xs-right">
    <input class="form-control" type="text" placeholder="Search">
    <button class="btn btn-outline-success" type="submit">Search</button>
  </form>
</nav>

正如评论中指出的 (link)

Answer 2

将你淹没的 html 部分修改为：

<li class="nav-item dropdown">
  <div ngbDropdown class="d-inline-block">
    <button class="btn btn-outline-primary" id="dropdownMenu1" 
      **ngbDropdownToggle**>use Attrib ngbDropdownToggle</button>

    <!-- use  ngbDropdownMenu -->
    <div **ngbDropdownMenu** class="dropdown-menu" aria-labelledby="dropdownMenu1">
      <button class="dropdown-item">Action - 1</button>
      <button class="dropdown-item">Another Action</button>
      <button class="dropdown-item">Something else is here</button>
    </div>
  </div>
</li>    

Answer 3

我最终做了这样的事情：

在 html 模板中我有这个代码：

 <nav id="mainNavbar" class="navbar navbar-expand-lg navbar-dark bg-dark fixed-top">
        <a class="navbar-brand" href="#">Navbar</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse"
           data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent"
           aria-expanded="false" aria-label="Toggle navigation
           (click)="toggleCollapsed()">
          <span class="navbar-toggler-icon"></span>
        </button>
        <div id="navbarSupportedContent" [ngClass]="{'collapse': collapsed, 'navbar-collapse': true}">
......
</nav>

在组件中我有这个

 export class NavComponent {
      collapsed = true;
      toggleCollapsed(): void {
        this.collapsed = !this.collapsed;
      }
 }