无法在Angular中的Bootstrap 4中切换Navbar

Question

为什么我不能在使用bootstrap 4在角度4中调整大小到移动屏幕时切换导航栏.我将它包含在脚本和样式的角度cli中,来自bootstrap的节点模块.我的代码中是否缺少某些内容？请检查下面.有什么不对？请帮忙

<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
  <a class="navbar-brand" href="#">Dashboard</a>
  <button class="navbar-toggler d-lg-none" type="button" data-toggle="collapse" data-target="#navbarsExampleDefault" aria-controls="navbarsExampleDefault" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>

  <div class="collapse navbar-collapse" id="navbarsExampleDefault">
    <ul class="navbar-nav mr-auto">
      <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="#">Settings</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Profile</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Help</a>
      </li>
    </ul>
    <form class="form-inline mt-2 mt-md-0">
      <input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search">
      <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
    </form>
  </div>
</nav>

.angular-cli.json

 "styles": [
    "styles.css",
     "../node_modules/bootstrap/dist/css/bootstrap.min.css"
  ],
  "scripts": [

    "../node_modules/popper.js/dist/umd/popper.min.js",
    "../node_modules/jquery/dist/jquery.min.js",
    "../node_modules/bootstrap/dist/js/bootstrap.min.js"

  ],

的package.json

      {
  "name": "dashboard2",
  "version": "0.0.0",
  "license": "MIT",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "^4.0.0",
    "@angular/common": "^4.0.0",
    "@angular/compiler": "^4.0.0",
    "@angular/core": "^4.0.0",
    "@angular/forms": "^4.0.0",
    "@angular/http": "^4.0.0",
    "@angular/platform-browser": "^4.0.0",
    "@angular/platform-browser-dynamic": "^4.0.0",
    "@angular/router": "^4.0.0",
    "bootstrap": "^4.0.0-beta",
    "core-js": "^2.4.1",
    "jquery": "^3.2.1",
    "popper.js": "^1.12.5",
    "rxjs": "^5.4.1",
    "zone.js": "^0.8.14"
  },
  "devDependencies": {
    "@angular/cli": "1.2.7",
    "@angular/compiler-cli": "^4.0.0",
    "@angular/language-service": "^4.0.0",
    "@types/jasmine": "~2.5.53",
    "@types/jasminewd2": "~2.0.2",
    "@types/node": "~6.0.60",
    "codelyzer": "~3.0.1",
    "jasmine-core": "~2.6.2",
    "jasmine-spec-reporter": "~4.1.0",
    "karma": "~1.7.0",
    "karma-chrome-launcher": "~2.1.1",
    "karma-cli": "~1.0.1",
    "karma-coverage-istanbul-reporter": "^1.2.1",
    "karma-jasmine": "~1.1.0",
    "karma-jasmine-html-reporter": "^0.2.2",
    "protractor": "~5.1.2",
    "ts-node": "~3.0.4",
    "tslint": "~5.3.2",
    "typescript": "~2.3.3"
  }
}

Answer 1

看起来你可能一直在从Bootstrap 看这个例子.我做了,并有同样的问题.

问题是它不是一个有角度的例子,所以它不起作用.要使其工作,您必须使用(click)事件和变量.所以将模板更改为

<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark">
  <a class="navbar-brand" href="#">Dashboard</a>
  <button class="navbar-toggler d-lg-none" type="button" (click)="isCollapsed = !isCollapsed" [attr.aria-expanded]="!isCollapsed" aria-controls="navbarsExampleDefault" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>

  <div class="collapse navbar-collapse" id="navbarsExampleDefault" [ngbCollapse]="isCollapsed">
    <ul class="navbar-nav mr-auto">
      <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="#">Settings</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Profile</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Help</a>
      </li>
    </ul>
    <form class="form-inline mt-2 mt-md-0">
      <input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search">
      <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
    </form>
  </div>
</nav>

如果您希望在默认情况下折叠菜单,则应在类中将变量设置为true(在组件的.ts文件中) public isCollapsed = true;

这是一个吸烟者

还有一件事; 如果导航器位于共享模块中,则必须记住在此处导入NgbCollapseModule.

也就是说,你的shared.module.ts应该是:

import { NgModule } from '@angular/core';
import { NgbCollapseModule } from '@ng-bootstrap/ng-bootstrap';
/*Plus all your other modules*/

@NgModule({
  imports: [NgbCollapseModule],
  declarations: [],
  exports: []
})
export class SharedModule {}

Answer 2

@Joseph,看起来你没有安装bootstrap(和bootstrap本身)的依赖项,导航栏切换工作.

如果打开终端或命令行并导航到包含package.json文件的目录,请运行以下命令:

npm install --save jquery
npm install --save popper.js
npm install --save bootstrap@4.0.0-beta

这些命令将为您的项目安装必需的依赖项.他们在他们正在做的事情相当明确的,但如果你需要刷新他们在做什么,或者他们是如何工作的,我建议在看的文件npm install位于这里.

安装完成后,您需要确保将它们包含在.angular-cli.json文件中,这样您就可以使用它们.

Answer 3

此示例提供汉堡包图标的切换功能(换句话说,如果它在响应模式下运行,则为整个导航栏)以及切换下拉菜单项.

它使用ng-bootstrap,但我更愿意使用本机Bootstrap导航栏支持,而不是做这个"黑客"!？

显然其他人也在努力解决同样的问题:https://github.com/twbs/bootstrap/issues/24227

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">ApplicationName</a>
  <button class="navbar-toggler" type="button" (click)="toggleNavbar = !toggleNavbar">
    <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" [ngbCollapse]="!toggleNavbar">
    <ul class="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="#">Features</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Pricing</a>
      </li>
      <li ngbDropdown class="nav-item">
        <a class="nav-link" id="navbarDropdownMenuLink" ngbDropdownToggle aria-haspopup="true" aria-expanded="false">
          Dropdown link
        </a>
        <div ngbDropdownMenu aria-labelledby="navbarDropdownMenuLink">
          <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>
  </div>
</nav>

Answer 4

如前所述，您需要一个属性（例如isShown最初为false），然后使用

[ngClass]="{ 'show': isShown }" 

这里

<div class="collapse navbar-collapse" [ngClass]="{ 'show': isShown }" id="navbarSupportedContent" >

链接上的点击事件可确保在跟随链接时菜单再次折叠

[ngClass]="{ 'show': isShown }" 

<div class="collapse navbar-collapse" [ngClass]="{ 'show': isShown }" id="navbarSupportedContent" >