Add routing

[JorisSchelfaut]

Conceptual preview of routing

This tutorial introduces routing in Angular. Routing is the ability to navigate from one component in the application to another. In Single Page Applications (SPA), only parts of the page are updated to represent the requested view for the user.

The Angular Router enables users to declare routes and specify which component should be displayed on the screen if that route is requested by the application.

In this lesson, you will enable routing in your application to navigate to the details page.

1. Create a default details component

From the terminal, enter the following command to create the DetailsComponent:

ng generate component details

This component will represent the details page that provides more information on a given housing location.

2. Add routing to the application

1. In the src/app directory, create a file called routes.ts. This file is where we will define the routes in the application.

2. In main.ts, make the following updates to enable routing in the application:

   1. Import the routes file and the provideRouter function:

      import {provideRouter} from '@angular/router';
      import routeConfig from './app/routes';

   2. Update the call to bootstrapApplication to include the routing configuration:

      bootstrapApplication(AppComponent, {
        providers: [provideProtractorTestingSupport(), provideRouter(routeConfig)],
      }).catch((err) => console.error(err));

   3. In src/app/app.component.ts, update the component to use routing:

      1. Add a file level import for RoutingModule:

         import {RouterModule} from '@angular/router';

      2. Add RouterModule to the @Component metadata imports

         imports: [HomeComponent, RouterModule],

      3. In the template property, replace the tag with the directive and add a link back to the home page. Your code should match this code:

           template: `
             <main>
               <a [routerLink]="['/']">
                 <header class="brand-name">
                   <img class="brand-logo" src="/assets/logo.svg" alt="logo" aria-hidden="true" />
                 </header>
               </a>
               <section class="content">
                 <router-outlet></router-outlet>
               </section>
             </main>

3. Add route to new component

In the previous step you removed the reference to the component in the template. In this step, you will add a new route to that component.

1. In routes.ts, perform the following updates to create a route.

   1. Add a file level imports for the HomeComponent, DetailsComponent and the Routes type that you'll use in the route definitions.

      import {Routes} from '@angular/router';
      import {HomeComponent} from './home/home.component';
      import {DetailsComponent} from './details/details.component';

   2. Define a variable called routeConfig of type Routes and define two routes for the app:

      const routeConfig: Routes = [
        {
          path: '',
          component: HomeComponent,
          title: 'Home page',
        },
        {
          path: 'details/:id',
          component: DetailsComponent,
          title: 'Home details',
        },
      ];
      export default routeConfig;

      The entries in the routeConfig array represent the routes in the application. The first entry navigates to the HomeComponent whenever the url matches ''. The second entry uses some special formatting that will be revisited in a future lesson.

2. Save all changes and confirm that the application works in the browser. The application should still display the list of housing locations.