1c-brief-introduction-to-angular.md

1c - Brief Introduction To Angular

1. Refactor to use lazy loaded User module

ng g module user --routing

2. Move all User related folders into the user module folder

3. Remove all references to Users in App module

{% code title="src/app/app.module.ts" %}

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { HomeComponent } from './home/home.component';
import { HttpClientModule } from '@angular/common/http';

@NgModule({
  declarations: [
    AppComponent,
    HomeComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    HttpClientModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

{% endcode %}

4. Change routes to lazy loaded routes

{% code title="src/app/app-routing.module.ts" %}

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { HomeComponent } from './home/home.component';

const routes: Routes = [
  { path: '', component: HomeComponent },
  { path: 'users', loadChildren: 'src/app/user/user.module#UserModule' },   ///changed
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { }

{% endcode %}

5. Add UserList component as feature module route

{% code title="src/app/user/user-routing.module.ts" %}

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { UserListComponent } from './user-list/user-list.component'; // changed

const routes: Routes = [
  { path: '', component: UserListComponent },    //changed
];

@NgModule({
  imports: [RouterModule.forChild(routes)],
  exports: [RouterModule]
})
export class UserRoutingModule { }

{% endcode %}

6. Declare UserList component in new User module

{% code title="src/app/user/user.module.ts" %}

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { UserListComponent } from './user-list/user-list.component';   //added
import { UserRoutingModule } from './user-routing.module';

@NgModule({
  imports: [
    CommonModule,
    UserRoutingModule
  ],
  declarations: [
    UserListComponent            //added
  ]
})
export class UserModule { }

{% endcode %}

7. Add button on App component to navigate to UserList or Home component

{% code title="src/app/app.component.html" %}

<h1>The App</h1>
​
<div>
  <button [routerLink]="['/']" routerLinkActive="router-link-active" >home</button>
  <button [routerLink]="['/users']" routerLinkActive="router-link-active" >users</button>
</div>

<!-- <app-home></app-home> -->
<router-outlet></router-outlet>

{% endcode %}

8. Run the application and inspect the lazy loaded JavaScript

Extras

1. Add extra project to CLI App

As of Angular CLI version 6+ you can now have multiple projects in an Angular app. It is early days and no support for sharing modules between apps and best practices or schematics made. That is what Nx can help with. You can read more on the Angular CLI limited docs ​https://github.com/angular/angular-cli/wiki/stories-multiple-projects

In the terminal run

ng generate application my-other-app

2. Add npm package library to your app

Angular CLI v6 comes with library support via ng-packagr plugged into the build system we use in Angular CLI, together with schematics for generating a library.

https://github.com/angular/angular-cli/wiki/stories-create-library

In the terminal run

ng generate library my-lib