Troubleshooting the malfunction of the Angular 2 Tour of Heroes project following the separation of the app

Recently, I encountered a challenge while following a tutorial on learning Angular 2. Everything was going smoothly until I reached the point where I had to divide appcomponent into heroescomponent & appcomponent.

Is there anyone else who has faced this issue or can help identify the problem?

app.component.ts

import { Component }       from 'angular2/core';
import { HeroService }     from './hero.service';
import { HeroesComponent } from './heroes.component';
import {RouteConfig, ROUTER_DIRECTIVES, ROUTER_PROVIDERS} from 'angular2/router';
import {DashboardComponent} from './dashboard.component';
import {HeroDetailComponent} from "./hero-detail.component";

@Component({
    selector: 'my-app',
    template: `
        <h1>{{title}}</h1>
        <nav
            <a [routerLink]="['Dashboard']">Dashboard</a>
            <a [routerLink]="['Heroes']">Heroes</a>
        </nav>

        <router-outlet></router-outlet>
      `,

    styleUrls: ['app/app.component.css'],
    directives: [ROUTER_DIRECTIVES],
    providers: [
        ROUTER_PROVIDERS,
        HeroService
    ]
})

@RouteConfig([
    {
        path: '/heroes',
        name: 'Heroes',
        component: HeroesComponent
    },
    {
        path: '/dashboard',
        name: 'Dashboard',
        component: DashboardComponent,
        useAsDefault: true
    },
    {
        path: '/detail/:id',
        name: 'HeroDetail',
        component: HeroDetailComponent
    }
])

export class AppComponent {
    title = 'Tour of Heroes';
}

heroes.component.ts

import {Component, OnInit} from 'angular2/core';
import {Hero} from './hero';
import {HeroDetailComponent} from './hero-detail.component';
import {HeroService} from './hero.service';
import {Router} from 'angular2/router';

@Component({
    selector: 'my-heroes',
    templateUrl: 'app/heroes.component.html',
    styleUrls: ['app/heroes.component.css'],
    directives: [HeroDetailComponent]
})

export class HeroesComponent implements OnInit{
    heroes: Hero[];
    selectedHero: Hero;

    constructor(
        private _heroService: HeroService,
        private _router: Router
    ) {}

    ngOnInit() {
        this.getHeroes();
    }

    getHeroes() {
        this._heroService.getHeroes().then(heroes => this.heroes = heroes);
    }

    onSelect(hero: Hero) {
        this.selectedHero = hero;
    }

    gotoDetail() {
        this._router.navigate(['HeroDetail', { id: this.selectedHero.id}]);
    }
}

main.ts

import {bootstrap} from 'angular2/platform/browser'
import {AppComponent} from './app.component.ts'

bootstrap(AppComponent);

Tour of Heroes Part 5: Splitting the appcomponent

Answer №1

The nav opening tag is missing the closing ">".

It should be

<nav>
    <a [routerLink]="['Dashboard']">Dashboard</a>
    <a [routerLink]="['Heroes']">Heroes</a>
</nav>

Instead of

<nav
    <a [routerLink]="['Dashboard']">Dashboard</a>
    <a [routerLink]="['Heroes']">Heroes</a>
</nav>

Here is a plunker

Answer №2

If you're still struggling with the same issue, I experienced a similar problem during my own project.

After spending some time troubleshooting why my component wasn't loading, I realized that a recent code refactor in my AppComponent (renamed to HeroesComponent) also required updating references in main.ts.

The refactor looked like this:

import {bootstrap} from "@angular/platform-browser-dynamic";
import {HeroesComponent} from "./heroes.component";

bootstrap(HeroesComponent);

It became clear that I was referencing the wrong component.

To resolve the issue, I made the following correction:

import {bootstrap} from "@angular/platform-browser-dynamic";
import {AppComponent} from "./app.component";

bootstrap(AppComponent);

And just like that, the app started loading properly again.

I hope this solution proves helpful for you as well.

Answer №3

My tutorial tour of heroes application has suddenly become unresponsive in the routing chapter, despite its previous well-behaved behavior. I've typically resolved issues by analyzing http response codes, but now I'm encountering 304 and 200 errors.

Instead of painstakingly checking every element for stray angle brackets, is there a more efficient way to troubleshoot this problem? Currently, all I see is a blank white rectangle with "Loading AppComponent content here ..." in the corner. Is there a log that can provide insight into what's causing this issue?

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