Presentation & Container Components in Ember

blog-comment.component.js

import Ember from 'ember';

const BlogCommentComponent = Ember.Component.extend({
});

BlogCommentComponent.reopenClass({
  positionalParams: ['comment']
});

export default BlogCommentComponent;

blog-comment.template.hbs

<hr />

{{comment.body}}

blog-post.comments-for.component.js

import Ember from 'ember';
import { task, timeout } from 'ember-concurrency';

const COMMENTS = [
  { body: 'This is a comment' },
  { body: 'This is another comment' }
];

export default Ember.Component.extend({
  tagName: '',
  
  init() {
    this._super(...arguments);
    this.set('comments', []);
  },
  
  didInsertElement() {
    this._super(...arguments);
    this.get('loadComments').perform();
  },
  
  loadComments: task(function* () {
    // We use a timeout here to simulate the fact that fetching the comments takes some time
    // If we did not lazily load them, the initial page load would be extended by this 1000ms instead
    yield timeout(1000);
    
    this.set('comments', COMMENTS);
  })
});

blog-post.comments-for.template.hbs

{{yield comments}}

blog-post.component.js

import Ember from 'ember';

const { computed } = Ember;

const BlogPostComponent = Ember.Component.extend({
  title: computed.alias('blogPost.title'),
  body: computed.alias('blogPost.body')
});

BlogPostComponent.reopenClass({
  positionalParams: ['blogPost']
});

export default BlogPostComponent;

blog-post.template.hbs

<h1>{{title}}</h1>

{{body}}

{{#blog-post/comments-for blogPost as |comments|}}
  {{#each comments as |comment|}}
    {{blog-comment comment}}
  {{/each}}
{{/blog-post/comments-for}}

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  blogPost: {
    title: 'This is the blog post',
    body: 'We want to render the comments later on, after the main content has loaded. This makes a better experience for the user, since they get the content they care about immediately, and we can fill in less important stuff after the initial page load.'
  }
});

templates.application.hbs

{{blog-post blogPost}}

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": true,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1",
    "ember-concurrency": "0.8.7"
  }
}