Nested Array Template

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  list: [
    { name: "Apple", colors: ["Red","Yellow","Green"] },
    { name: "Orange", colors: ["Orange"] },
    { name: "Grape", colors: ["Green", "Purple"] }
  ],
  newGrape() {
   this.list[2].colors.pushObject('Red');
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>

<div>
{{#each list as |x|}}
	<div>{{x.name}} | {{x.colors.length}}</div>
{{/each}}
</div>

<br>

<button {{action newGrape}}>
Discover New Grape Color
</button>

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}