问题
I've been implementing ng2-bootstrap and Angular2.
I cannot figure out how to make the mobile navbar open / close.
Is this something that just isn't supported yet? Or am I missing something?
Update, html:
<nav class="navbar navbar-default">
<div class="container-fluid">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">
<img src="/logo.png" />
</a>
</div>
<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
<ul class="nav navbar-nav">
<li router-active>
<a [routerLink]=" ['Index'] ">Summary<span class="sr-only">(current)</span></a>
</li>
<li router-active>
<a [routerLink]=" ['Portfolio'] ">Portfolio<span class="sr-only">(current)</span></a>
</li>
<li router-active>
<a [routerLink]=" ['About'] ">About<span class="sr-only">(current)</span></a>
</li>
</ul>
<form class="navbar-form navbar-left" role="search">
<div class="form-group">
<input type="text" class="form-control" placeholder="Search">
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
<ul class="nav navbar-nav navbar-right">
<li dropdown keyboardNav="true">
<a href class="dropdown-toggle" role="button" aria-expanded="false" dropdownToggle>
<span class="glyphicon glyphicon-user" aria-hidden="true"></span>
Andrew Duncan
<span class="caret"></span>
</a>
<ul class="dropdown-menu" role="menu">
<li role="menuitem"><a class="dropdown-item" href="#">Account Settings</a></li>
<li role="menuitem"><a class="dropdown-item" href="#">Another action</a></li>
<li role="menuitem"><a class="dropdown-item" href="#">Something else here</a></li>
<li class="divider dropdown-divider"></li>
<li role="menuitem"><a class="dropdown-item" href="#">Logout</a></li>
</ul>
</li>
</ul>
</div>
</div>
Typescript:
/*
* Angular 2 decorators and services
*/
import { Component, ViewEncapsulation } from '@angular/core';
import { RouteConfig, Router } from '@angular/router-deprecated';
import { AppState } from './app.service';
import { Home } from './home';
import { RouterActive } from './router-active';
import { BUTTON_DIRECTIVES, DROPDOWN_DIRECTIVES } from '../../node_modules/ng2-bootstrap';
/*
* App Component
* Top Level Component
*/
@Component({
selector: 'app',
pipes: [ ],
providers: [ ],
directives: [
RouterActive,
BUTTON_DIRECTIVES,
DROPDOWN_DIRECTIVES ],
encapsulation: ViewEncapsulation.None,
styles: [
require('./app.css')
],
template: require('./app.html')
})
@RouteConfig([
{ path: '/', name: 'Index', component: Home, useAsDefault: true },
{ path: '/home', name: 'Home', component: Home },
// Async load a component using Webpack's require with es6-promise-loader and webpack `require`
{ path: '/about', name: 'About', loader: () => require('es6-promise!./about')('About') },
{ path: '/portfolio', name: 'Portfolio', loader: () => require('es6-promise!./portfolio')('Portfolio') }
])
export class App {
angularclassLogo = 'assets/img/angularclass-avatar.png';
loading = false;
url = 'https://twitter.com/AngularClass';
constructor(
public appState: AppState) {
}
ngOnInit() {
console.log('Initial App State', this.appState.state);
}
}
/*
* Please review the https://github.com/AngularClass/angular2-examples/ repo for
* more angular app examples that you may copy/paste
* (The examples may not be updated as quickly. Please open an issue on github for us to update it)
* For help or questions please contact us at @AngularClass on twitter
* or our chat on Slack at https://AngularClass.com/slack-join
*/
回答1:
You need to include and use the collapse directive
first you import the directiveimport { CollapseDirective } from 'ng2-bootstrap'
Include it in your components directives@Component({ directives: [CollapseDirective] })
Edit: As pointed out by Akkusativobjekt in the comments, Directives (in the current stable version of angular 2) are no longer placed in the @Component attribute.
They are included in the NgModule attribute.@NgModule({ declarations: [CollapseDirective] })
then in your controller create a variable to keep track of whether or not it's collapsedexport class MyController {
public isCollapsed: boolean = true;
}
and in your template the line that looks like this <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" >
you'll want to toggle the variable<button type="button" class="navbar-toggle collapsed" (click)="isCollapsed = !isCollapsed" >
And also in your template you'll want to change the line that says<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
to include the directive<div id="navbar" class="navbar-collapse collapse" [collapse]="isCollapsed">
Documentation for ng2-bootstrap collapse
Example of using the collapse directive in html
Documentation for NgModule
回答2:
I was able to do this using straight bootstrap4/jquery within my angular2 project by adding the same data-toggle and data-target attributes to the collapsible target div:
<nav class="navbar navbar navbar-dark bg-inverse navbar-sticky-top clearfix">
<div class="clearfix">
<a class="navbar-brand" href="#">MCR</a>
<button class="navbar-toggler hidden-sm-up float-xs-right" type="button" data-toggle="collapse"
data-target="#exCollapsingNavbar2" aria-controls="exCollapsingNavbar2" aria-expanded="false"
aria-label="Toggle navigation">
</button>
</div>
<div class="collapse navbar-toggleable-xs" id="exCollapsingNavbar2" data-toggle="collapse" data-target="#exCollapsingNavbar2">
<ul class="nav navbar-nav">
<li class="nav-item">
<a routerLink="/home" routerLinkActive="active" class="nav-link" href="#">Home</a>
</li>
<li class="nav-item">
<a routerLink="/collection" routerLinkActive="active" class="nav-link" href="#">Collection</a>
</li>
</ul>
</div>
I hope this might help someone as I struggled with this. Thanks to all above for putting me on the right track.
回答3:
While Seth's solution works absolutely fine as it is, I modified the collapsing logic. Instead of using the click event, I subscribe to the router events to collapse the menu only after successful navigation.
export class NavMenuComponent implements OnDestroy {
public isCollapsed: boolean = true;
private subscription: Subscription;
constructor(private router: Router) {
this.subscription = this.router.events.subscribe(s => {
if (s instanceof NavigationEnd) {
this.isCollapsed = true;
}
});
}
ngOnDestroy() {
this.subscription.unsubscribe();
}
}
回答4:
This is a limitation of navbar (https://github.com/valor-software/ngx-bootstrap/issues/540). So you need to manipulate the DOM element.
<div class="navbar-header page-scroll">
<button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-ex1-collapse">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" routerLink="/">
<img src="assets/images/logo.png">
</a>
</div>
<div class="collapse navbar-collapse navbar-ex1-collapse">
<ul class="nav navbar-nav navbar-right" >
<li class="hidden">
<a></a>
</li>
<li><a routerLink="/" (click)="onMenuClick()">Home</a></li>
<li><a routerLink="/about" (click)="onMenuClick()">About</a></li>
</ul>
</div>
And on .ts file your minimal code shoul be:
import { Component, ElementRef, Renderer } from '@angular/core';
export class HeaderComponent {
constructor(private el: ElementRef, private renderer: Renderer) {
}
onMenuClick() {
//this.el.nativeElement.querySelector('.navbar-ex1-collapse') get the DOM
//this.renderer.setElementClass('DOM-Element', 'css-class-you-want-to-add', false) if 3rd value is true
//it will add the css class. 'in' class is responsible for showing the menu, remove it.
this.renderer.setElementClass(this.el.nativeElement.querySelector('.navbar-ex1-collapse'), 'in', false);
}
}
来源：https://stackoverflow.com/questions/37438683/is-there-a-way-to-build-the-mobile-nav-bar-in-ng2-bootstrap