Tuto

package-lock.json

@@ -473,6 +473,11 @@
         }
       }
     },
+    "angular-in-memory-web-api": {
+      "version": "0.5.3",
+      "resolved": "https://registry.npmjs.org/angular-in-memory-web-api/-/angular-in-memory-web-api-0.5.3.tgz",
+      "integrity": "sha512-1QPwwXG8R/2s7EbHh13HDiJYsk4sdBHNxHJHZHJ/Kxb4T9OG+bb1kGcXzY9UrJkEVxOtUW0ozvL4p/HmeIEszg=="
+    },
     "ansi-html": {
       "version": "0.0.7",
       "resolved": "https://registry.npmjs.org/ansi-html/-/ansi-html-0.0.7.tgz",

package.json

@@ -21,6 +21,7 @@
     "@angular/platform-browser": "^5.2.0",
     "@angular/platform-browser-dynamic": "^5.2.0",
     "@angular/router": "^5.2.0",
+    "angular-in-memory-web-api": "^0.5.3",
     "core-js": "^2.4.1",
     "rxjs": "^5.5.6",
     "zone.js": "^0.8.19"

src/app/app-routing.module.ts

@@ -0,0 +1,18 @@
+import { NgModule } from '@angular/core';
+import { RouterModule, Routes } from '@angular/router';
+import { HeroesComponent } from './heroes/heroes.component';
+import { DashboardComponent } from './dashboard/dashboard.component';
+import { HeroDetailComponent } from './hero-detail/hero-detail.component';
+
+const routes: Routes = [
+  { path: 'heroes', component: HeroesComponent },
+  { path: 'dashboard', component: DashboardComponent },
+  { path: 'detail/:id', component: HeroDetailComponent },
+  { path: '', redirectTo: '/dashboard', pathMatch: 'full' }
+];
+
+@NgModule({
+  imports: [ RouterModule.forRoot(routes) ],
+  exports: [ RouterModule ]
+})
+export class AppRoutingModule { }

src/app/app.component.css

@@ -0,0 +1,29 @@
+/* AppComponent's private CSS styles */
+h1 {
+  font-size: 1.2em;
+  color: #999;
+  margin-bottom: 0;
+}
+h2 {
+  font-size: 2em;
+  margin-top: 0;
+  padding-top: 0;
+}
+nav a {
+  padding: 5px 10px;
+  text-decoration: none;
+  margin-top: 10px;
+  display: inline-block;
+  background-color: #eee;
+  border-radius: 4px;
+}
+nav a:visited, a:link {
+  color: #607D8B;
+}
+nav a:hover {
+  color: #039be5;
+  background-color: #CFD8DC;
+}
+nav a.active {
+  color: #039be5;
+}

src/app/app.component.html

@@ -1,20 +1,7 @@
-<!--The content below is only a placeholder and can be replaced.-->
+<h1> {{ title }}  </h1>
-<div style="text-align:center">
+<nav>
-  <h1>
+  <a routerLink="/dashboard">Dashboard</a>
-    Welcome to {{ title }}!
+  <a routerLink="/heroes">Heroes</a>
-  </h1>
+</nav>
-  <img width="300" alt="Angular Logo" src="data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNTAgMjUwIj4KICAgIDxwYXRoIGZpbGw9IiNERDAwMzEiIGQ9Ik0xMjUgMzBMMzEuOSA2My4ybDE0LjIgMTIzLjFMMTI1IDIzMGw3OC45LTQzLjcgMTQuMi0xMjMuMXoiIC8+CiAgICA8cGF0aCBmaWxsPSIjQzMwMDJGIiBkPSJNMTI1IDMwdjIyLjItLjFWMjMwbDc4LjktNDMuNyAxNC4yLTEyMy4xTDEyNSAzMHoiIC8+CiAgICA8cGF0aCAgZmlsbD0iI0ZGRkZGRiIgZD0iTTEyNSA1Mi4xTDY2LjggMTgyLjZoMjEuN2wxMS43LTI5LjJoNDkuNGwxMS43IDI5LjJIMTgzTDEyNSA1Mi4xem0xNyA4My4zaC0zNGwxNy00MC45IDE3IDQwLjl6IiAvPgogIDwvc3ZnPg==">
+<router-outlet></router-outlet>
-</div>
+<app-messages></app-messages>
-<h2>Here are some links to help you start: </h2>
-<ul>
-  <li>
-    <h2><a target="_blank" rel="noopener" href="https://angular.io/tutorial">Tour of Heroes</a></h2>
-  </li>
-  <li>
-    <h2><a target="_blank" rel="noopener" href="https://github.com/angular/angular-cli/wiki">CLI Documentation</a></h2>
-  </li>
-  <li>
-    <h2><a target="_blank" rel="noopener" href="https://blog.angular.io/">Angular blog</a></h2>
-  </li>
-</ul>
-

src/app/app.component.ts

@@ -6,5 +6,5 @@ import { Component } from '@angular/core';
   styleUrls: ['./app.component.css']
 })
 export class AppComponent {
-  title = 'app';
+  title = 'Tour of Heroes';
 }

src/app/app.module.ts

@@ -1,18 +1,48 @@
 import { BrowserModule } from '@angular/platform-browser';
 import { NgModule } from '@angular/core';
-
+import { FormsModule } from '@angular/forms';
+import { HttpClientModule } from '@angular/common/http';
 
 import { AppComponent } from './app.component';
+import { HeroesComponent } from './heroes/heroes.component';
+import { HeroDetailComponent } from './hero-detail/hero-detail.component';
+import { HeroService } from './hero.service';
+import { MessagesComponent } from './messages/messages.component';
+import { MessageService } from './message.service';
+import { AppRoutingModule } from './/app-routing.module';
+import { DashboardComponent } from './dashboard/dashboard.component';
+import { HeroSearchComponent } from './hero-search/hero-search.component';
+
+import { HttpClientInMemoryWebApiModule } from 'angular-in-memory-web-api';
+import { InMemoryDataService }  from './in-memory-data.service';
 
 
 @NgModule({
   declarations: [
-    AppComponent
+    AppComponent,
+    HeroesComponent,
+    HeroDetailComponent,
+    MessagesComponent,
+    DashboardComponent,
+    HeroSearchComponent
   ],
   imports: [
-    BrowserModule
+    BrowserModule,
+    FormsModule,
+    AppRoutingModule,
+    HttpClientModule,
+
+    // The HttpClientInMemoryWebApiModule module intercepts HTTP requests
+    // and returns simulated server responses.
+    // Remove it when a real server is ready to receive requests.
+    HttpClientInMemoryWebApiModule.forRoot(
+      InMemoryDataService, { dataEncapsulation: false }
+    )
+  ],
+  providers: [
+    HeroService,
+    MessageService,
   ],
-  providers: [],
   bootstrap: [AppComponent]
 })
 export class AppModule { }

src/app/dashboard/dashboard.component.css

@@ -0,0 +1,62 @@
+/* DashboardComponent's private CSS styles */
+[class*='col-'] {
+  float: left;
+  padding-right: 20px;
+  padding-bottom: 20px;
+}
+[class*='col-']:last-of-type {
+  padding-right: 0;
+}
+a {
+  text-decoration: none;
+}
+*, *:after, *:before {
+  -webkit-box-sizing: border-box;
+  -moz-box-sizing: border-box;
+  box-sizing: border-box;
+}
+h3 {
+  text-align: center; margin-bottom: 0;
+}
+h4 {
+  position: relative;
+}
+.grid {
+  margin: 0;
+}
+.col-1-4 {
+  width: 25%;
+}
+.module {
+  padding: 20px;
+  text-align: center;
+  color: #eee;
+  max-height: 120px;
+  min-width: 120px;
+  background-color: #607D8B;
+  border-radius: 2px;
+}
+.module:hover {
+  background-color: #EEE;
+  cursor: pointer;
+  color: #607d8b;
+}
+.grid-pad {
+  padding: 10px 0;
+}
+.grid-pad > [class*='col-']:last-of-type {
+  padding-right: 20px;
+}
+@media (max-width: 600px) {
+  .module {
+    font-size: 10px;
+    max-height: 75px; }
+}
+@media (max-width: 1024px) {
+  .grid {
+    margin: 0;
+  }
+  .module {
+    min-width: 60px;
+  }
+}

src/app/dashboard/dashboard.component.html

@@ -0,0 +1,11 @@
+<h3>Top Heroes</h3>
+<div class="grid grid-pad">
+  <a *ngFor="let hero of heroes" class="col-1-4"
+    routerLink="/detail/{{ hero.id }}">
+    <div class="module hero">
+      <h4>{{hero.name}}</h4>
+    </div>
+  </a>
+</div>
+
+<app-hero-search></app-hero-search>

src/app/dashboard/dashboard.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { DashboardComponent } from './dashboard.component';
+
+describe('DashboardComponent', () => {
+  let component: DashboardComponent;
+  let fixture: ComponentFixture<DashboardComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ DashboardComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(DashboardComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/dashboard/dashboard.component.ts

@@ -0,0 +1,24 @@
+import { Component, OnInit } from '@angular/core';
+import { Hero } from '../hero';
+import { HeroService } from '../hero.service';
+
+@Component({
+  selector: 'app-dashboard',
+  templateUrl: './dashboard.component.html',
+  styleUrls: ['./dashboard.component.css']
+})
+export class DashboardComponent implements OnInit {
+  heroes: Hero[] = [];
+
+  constructor(private heroService: HeroService) { }
+
+  ngOnInit() {
+    this.getHeroes();
+  }
+
+  getHeroes(): void {
+    this.heroService.getHeroes()
+      .subscribe(heroes => this.heroes = heroes.slice(1, 5));
+  }
+
+}

src/app/hero-detail/hero-detail.component.html

@@ -0,0 +1,12 @@
+<div *ngIf="hero">
+  <h2> {{ hero.name | uppercase }} Details</h2>
+  <div><span> id: {{ hero.id }} </span></div>
+  <div>
+    <label> name:
+      <input [(ngModel)]="hero.name" placeholder="name">
+    </label>
+  </div>
+</div>
+
+<button (click)="save()"> save </button>
+<button (click)="goBack()">go back</button>

src/app/hero-detail/hero-detail.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { HeroDetailComponent } from './hero-detail.component';
+
+describe('HeroDetailComponent', () => {
+  let component: HeroDetailComponent;
+  let fixture: ComponentFixture<HeroDetailComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ HeroDetailComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(HeroDetailComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/hero-detail/hero-detail.component.ts

@@ -0,0 +1,41 @@
+import { Component, OnInit, Input } from '@angular/core';
+import { Hero } from '../hero';
+import { ActivatedRoute } from '@angular/router';
+import { Location } from '@angular/common';
+
+import { HeroService }  from '../hero.service';
+
+@Component({
+  selector: 'app-hero-detail',
+  templateUrl: './hero-detail.component.html',
+  styleUrls: ['./hero-detail.component.css']
+})
+export class HeroDetailComponent implements OnInit {
+
+  @Input() hero: Hero;
+
+  constructor(
+    private route: ActivatedRoute,
+    private heroService: HeroService,
+    private location: Location
+  ) { }
+
+  ngOnInit() {
+    this.getHero();
+  }
+
+  getHero(): void {
+    const id = +this.route.snapshot.paramMap.get('id');
+    this.heroService.getHero(id)
+      .subscribe(h => this.hero = h);
+  }
+
+  goBack(): void {
+    this.location.back();
+  }
+
+  save(): void {
+    this.heroService.updateHero(this.hero)
+        .subscribe(() => this.goBack());
+  }
+}

src/app/hero-search/hero-search.component.css

@@ -0,0 +1,39 @@
+/* HeroSearch private styles */
+.search-result li {
+  border-bottom: 1px solid gray;
+  border-left: 1px solid gray;
+  border-right: 1px solid gray;
+  width:195px;
+  height: 16px;
+  padding: 5px;
+  background-color: white;
+  cursor: pointer;
+  list-style-type: none;
+}
+
+.search-result li:hover {
+  background-color: #607D8B;
+}
+
+.search-result li a {
+  color: #888;
+  display: block;
+  text-decoration: none;
+}
+
+.search-result li a:hover {
+  color: white;
+}
+.search-result li a:active {
+  color: white;
+}
+#search-box {
+  width: 200px;
+  height: 20px;
+}
+
+
+ul.search-result {
+  margin-top: 0;
+  padding-left: 0;
+}

src/app/hero-search/hero-search.component.html

@@ -0,0 +1,13 @@
+<div id="search-component">
+  <h4>Hero Search</h4>
+
+  <input #searchBox id="search-box" (keyup)="search(searchBox.value)" />
+
+  <ul class="search-result">
+    <li *ngFor="let hero of heroes$ | async" >
+      <a routerLink="/detail/{{hero.id}}">
+        {{hero.name}}
+      </a>
+    </li>
+  </ul>
+</div>

src/app/hero-search/hero-search.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { HeroSearchComponent } from './hero-search.component';
+
+describe('HeroSearchComponent', () => {
+  let component: HeroSearchComponent;
+  let fixture: ComponentFixture<HeroSearchComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ HeroSearchComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(HeroSearchComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/hero-search/hero-search.component.ts

@@ -0,0 +1,43 @@
+import { Component, OnInit } from '@angular/core';
+
+import { Observable } from 'rxjs/Observable';
+import { Subject }    from 'rxjs/Subject';
+import { of }         from 'rxjs/observable/of';
+
+import {
+   debounceTime, distinctUntilChanged, switchMap
+ } from 'rxjs/operators';
+
+import { Hero } from '../hero';
+import { HeroService } from '../hero.service';
+
+@Component({
+  selector: 'app-hero-search',
+  templateUrl: './hero-search.component.html',
+  styleUrls: [ './hero-search.component.css' ]
+})
+
+export class HeroSearchComponent implements OnInit {
+  heroes$: Observable<Hero[]>;
+  private searchTerms = new Subject<string>();
+
+  constructor(private heroService: HeroService) {}
+
+  // Push a search term into the observable stream.
+  search(term: string): void {
+    this.searchTerms.next(term);
+  }
+
+  ngOnInit(): void {
+    this.heroes$ = this.searchTerms.pipe(
+      // wait 300ms after each keystroke before considering the term
+      debounceTime(300),
+
+      // ignore new term if same as previous term
+      distinctUntilChanged(),
+
+      // switch to new search observable each time the term changes
+      switchMap((term: string) => this.heroService.searchHeroes(term)),
+    );
+  }
+}

src/app/hero.service.spec.ts

@@ -0,0 +1,15 @@
+import { TestBed, inject } from '@angular/core/testing';
+
+import { HeroService } from './hero.service';
+
+describe('HeroService', () => {
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [HeroService]
+    });
+  });
+
+  it('should be created', inject([HeroService], (service: HeroService) => {
+    expect(service).toBeTruthy();
+  }));
+});

src/app/hero.service.ts

@@ -0,0 +1,102 @@
+import { Injectable } from '@angular/core';
+import { Hero } from './hero';
+import { HEROES } from './mock-heroes';
+import { Observable } from 'rxjs/Observable';
+import { of } from 'rxjs/observable/of';
+import { MessageService } from './message.service';
+import { HttpClient, HttpHeaders } from '@angular/common/http';
+import { catchError, map, tap } from 'rxjs/operators';
+
+const httpOptions = {
+  headers: new HttpHeaders({ 'Content-Type': 'application/json' })
+};
+
+@Injectable()
+export class HeroService {
+
+  private heroesUrl = 'api/heroes';
+
+  constructor(
+    private http: HttpClient,
+    private messageService: MessageService
+  ) { }
+
+  getHeroes(): Observable<Hero[]> {
+    return this.http.get<Hero[]>(this.heroesUrl)
+        .pipe(
+          tap(heroes => this.log('fetched heroes')),
+          catchError(this.handleError('getHeroes', []))
+        );
+  }
+
+  getHero(id: number): Observable<Hero> {
+    const heroUrl = `${this.heroesUrl}/${id}`;
+    return this.http.get<Hero>(heroUrl)
+        .pipe(
+          tap(_ => this.log(`fetched hero id=${id}`)),
+          catchError(this.handleError<Hero>(`getHero id=${id}`))
+        );
+  }
+
+  updateHero(hero: Hero): Observable<any> {
+    return this.http.put(this.heroesUrl, hero, httpOptions)
+        .pipe(
+          tap(_ => this.log(`updated hero id=${hero.id}`)),
+          catchError(this.handleError<any>('updateHero'))
+        );
+  }
+
+  addHero(hero: Hero): Observable<Hero> {
+    return this.http.post(this.heroesUrl, hero, httpOptions)
+        .pipe(
+          tap(_ => this.log(`added hero id=${hero.id}`)),
+          catchError(this.handleError<any>('addHero'))
+        );
+  }
+
+  /** DELETE: delete the hero from the server */
+  deleteHero (hero: Hero | number): Observable<Hero> {
+    const id = typeof hero === 'number' ? hero : hero.id;
+    const url = `${this.heroesUrl}/${id}`;
+
+    return this.http.delete<Hero>(url, httpOptions).pipe(
+      tap(_ => this.log(`deleted hero id=${id}`)),
+      catchError(this.handleError<Hero>('deleteHero'))
+    );
+  }
+
+  searchHeroes(term: string): Observable<Hero[]> {
+    term = term.trim();
+    if (!term) { return of([]); }
+    return this.http.get<Hero[]>(`api/heroes/?name=${term}`)
+        .pipe(
+          tap(_ => this.log(`found heroes matching "${term}"`)),
+          catchError(this.handleError<Hero[]>('searchHeroes', []))
+        );
+  }
+
+  private log(message: string) {
+    this.messageService.add('HeroService: ' + message);
+  }
+
+  /**
+   * Handle Http operation that failed.
+   * Let the app continue.
+   * @param operation - name of the operation that failed
+   * @param result - optional value to return as the observable result
+   */
+  private handleError<T> (operation = 'operation', result?: T) {
+    return (error: any): Observable<T> => {
+
+      // TODO: send the error to remote logging infrastructure
+      console.error(error); // log to console instead
+
+      // TODO: better job of transforming error for user consumption
+      this.log(`${operation} failed: ${error.message}`);
+
+      // Let the app keep running by returning an empty result.
+      return of(result as T);
+    };
+  }
+
+}

src/app/hero.ts

@@ -0,0 +1,4 @@
+export class Hero {
+  id: number;
+  name: string;
+}

src/app/heroes/heroes.component.css

@@ -0,0 +1,73 @@
+/* HeroesComponent's private CSS styles */
+.heroes {
+  margin: 0 0 2em 0;
+  list-style-type: none;
+  padding: 0;
+  width: 15em;
+}
+.heroes li {
+  position: relative;
+  cursor: pointer;
+  background-color: #EEE;
+  margin: .5em;
+  padding: .3em 0;
+  height: 1.6em;
+  border-radius: 4px;
+}
+
+.heroes li:hover {
+  color: #607D8B;
+  background-color: #DDD;
+  left: .1em;
+}
+
+.heroes a {
+  color: #888;
+  text-decoration: none;
+  position: relative;
+  display: block;
+  width: 250px;
+}
+
+.heroes a:hover {
+  color:#607D8B;
+}
+
+.heroes .badge {
+  display: inline-block;
+  font-size: small;
+  color: white;
+  padding: 0.8em 0.7em 0 0.7em;
+  background-color: #607D8B;
+  line-height: 1em;
+  position: relative;
+  left: -1px;
+  top: -4px;
+  height: 1.8em;
+  min-width: 16px;
+  text-align: right;
+  margin-right: .8em;
+  border-radius: 4px 0 0 4px;
+}
+
+.button {
+  background-color: #eee;
+  border: none;
+  padding: 5px 10px;
+  border-radius: 4px;
+  cursor: pointer;
+  cursor: hand;
+  font-family: Arial;
+}
+
+button:hover {
+  background-color: #cfd8dc;
+}
+
+button.delete {
+  position: relative;
+  left: 194px;
+  top: -32px;
+  background-color: gray !important;
+  color: white;
+}

src/app/heroes/heroes.component.html

@@ -0,0 +1,21 @@
+<h2> My Heroes </h2>
+
+<div>
+  <label>Hero name:
+    <input #heroName />
+  </label>
+  <!-- (click) passes input value to add() and then clears the input -->
+  <button (click)="add(heroName.value); heroName.value=''">
+    add
+  </button>
+</div>
+
+<ul class="heroes">
+  <li *ngFor="let hero of heroes">
+    <a routerLink="/detail/{{ hero.id }}">
+      <span class="badge">{{ hero.id }}</span> {{ hero.name }}
+    </a>
+    <button class="delete" title="delete hero"
+      (click)="delete(hero)">x</button>
+  </li>
+</ul>

src/app/heroes/heroes.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { HeroesComponent } from './heroes.component';
+
+describe('HeroesComponent', () => {
+  let component: HeroesComponent;
+  let fixture: ComponentFixture<HeroesComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ HeroesComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(HeroesComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/heroes/heroes.component.ts

@@ -0,0 +1,43 @@
+import { Component, OnInit } from '@angular/core';
+import { Hero } from '../hero';
+import { HeroService } from '../hero.service';
+
+@Component({
+  selector: 'app-heroes',
+  templateUrl: './heroes.component.html',
+  styleUrls: ['./heroes.component.css']
+})
+export class HeroesComponent implements OnInit {
+
+  heroes: Hero[];
+
+  selectedHero: Hero;
+
+  constructor(private heroService: HeroService) { }
+
+  ngOnInit() {
+    this.getHeroes();
+  }
+
+  onSelect(h: Hero): void {
+    this.selectedHero = h;
+  }
+
+  getHeroes():void {
+    this.heroService.getHeroes()
+      .subscribe(heroes => this.heroes = heroes);
+  }
+
+  add(name: string): void {
+    name = name.trim();
+    if (!name) { return; }
+    this.heroService.addHero( { name } as Hero)
+        .subscribe(hero => this.heroes.push(hero));
+  }
+
+  delete(hero: Hero): void {
+    this.heroes = this.heroes.filter(h => h !== hero);
+    this.heroService.deleteHero(hero).subscribe();
+  }
+
+}

src/app/in-memory-data.service.ts

@@ -0,0 +1,19 @@
+import { InMemoryDbService } from 'angular-in-memory-web-api';
+
+export class InMemoryDataService implements InMemoryDbService {
+  createDb() {
+    const heroes = [
+      { id: 11, name: 'Mr. Nice' },
+      { id: 12, name: 'Narco' },
+      { id: 13, name: 'Bombasto' },
+      { id: 14, name: 'Celeritas' },
+      { id: 15, name: 'Magneta' },
+      { id: 16, name: 'RubberMan' },
+      { id: 17, name: 'Dynama' },
+      { id: 18, name: 'Dr IQ' },
+      { id: 19, name: 'Magma' },
+      { id: 20, name: 'Tornado' }
+    ];
+    return {heroes};
+  }
+}

src/app/message.service.spec.ts

@@ -0,0 +1,15 @@
+import { TestBed, inject } from '@angular/core/testing';
+
+import { MessageService } from './message.service';
+
+describe('MessageService', () => {
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [MessageService]
+    });
+  });
+
+  it('should be created', inject([MessageService], (service: MessageService) => {
+    expect(service).toBeTruthy();
+  }));
+});

src/app/message.service.ts

@@ -0,0 +1,16 @@
+import { Injectable } from '@angular/core';
+
+@Injectable()
+export class MessageService {
+
+  messages: string[] = [];
+
+  add(message: string) {
+    this.messages.push(message);
+  }
+
+  clear() {
+    this.messages = [];
+  }
+
+}

src/app/messages/messages.component.css

@@ -0,0 +1,35 @@
+/* MessagesComponent's private CSS styles */
+h2 {
+  color: red;
+  font-family: Arial, Helvetica, sans-serif;
+  font-weight: lighter;
+}
+body {
+  margin: 2em;
+}
+body, input[text], button {
+  color: crimson;
+  font-family: Cambria, Georgia;
+}
+
+button.clear {
+  font-family: Arial;
+  background-color: #eee;
+  border: none;
+  padding: 5px 10px;
+  border-radius: 4px;
+  cursor: pointer;
+  cursor: hand;
+}
+button:hover {
+  background-color: #cfd8dc;
+}
+button:disabled {
+  background-color: #eee;
+  color: #aaa;
+  cursor: auto;
+}
+button.clear {
+  color: #888;
+  margin-bottom: 12px;
+}

src/app/messages/messages.component.html

@@ -0,0 +1,8 @@
+<div *ngIf="messageService.messages.length">
+
+  <h2>Messages</h2>
+  <button class="clear"
+          (click)="messageService.clear()">clear</button>
+  <div *ngFor='let message of messageService.messages'> {{message}} </div>
+
+</div>

src/app/messages/messages.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { MessagesComponent } from './messages.component';
+
+describe('MessagesComponent', () => {
+  let component: MessagesComponent;
+  let fixture: ComponentFixture<MessagesComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ MessagesComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(MessagesComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/messages/messages.component.ts

@@ -0,0 +1,16 @@
+import { Component, OnInit } from '@angular/core';
+import { MessageService } from '../message.service';
+
+@Component({
+  selector: 'app-messages',
+  templateUrl: './messages.component.html',
+  styleUrls: ['./messages.component.css']
+})
+export class MessagesComponent implements OnInit {
+
+  constructor(public messageService: MessageService) { }
+
+  ngOnInit() {
+  }
+
+}

src/app/mock-heroes.ts

@@ -0,0 +1,14 @@
+import { Hero } from './hero';
+
+export const HEROES: Hero[] = [
+  { id: 11, name: 'Mr. Nice' },
+  { id: 12, name: 'Narco' },
+  { id: 13, name: 'Bombasto' },
+  { id: 14, name: 'Celeritas' },
+  { id: 15, name: 'Magneta' },
+  { id: 16, name: 'RubberMan' },
+  { id: 17, name: 'Dynama' },
+  { id: 18, name: 'Dr IQ' },
+  { id: 19, name: 'Magma' },
+  { id: 20, name: 'Tornado' }
+];

src/styles.css

@@ -1 +1,23 @@
 /* You can add global styles to this file, and also import other style files */
+/* Application-wide Styles */
+h1 {
+  color: #369;
+  font-family: Arial, Helvetica, sans-serif;
+  font-size: 250%;
+}
+h2, h3 {
+  color: #444;
+  font-family: Arial, Helvetica, sans-serif;
+  font-weight: lighter;
+}
+body {
+  margin: 2em;
+}
+body, input[text], button {
+  color: #888;
+  font-family: Cambria, Georgia;
+}
+/* everywhere else */
+* {
+  font-family: Arial, Helvetica, sans-serif;
+}