loading substates

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

router.js

import Ember from 'ember';
import config from './config/environment';

const Router = Ember.Router.extend({
  location: 'none',
  rootURL: config.rootURL
});

Router.map(function() {
  this.route('a', function() {
    this.route('b');
  });
});

export default Router;

routes.a.js

import Ember from 'ember';
const { Route, RSVP } = Ember;

export default Route.extend({
  model() {
    return new RSVP.Promise(() => { });
  }
});

templates.a-loading.hbs

<p>a-loading</p>

templates.a.b.hbs

<p>b</p>

templates.application.hbs

<h3>application</h3>
{{#link-to "a.b"}}
  Go to a.b
{{/link-to}}
<br>
{{outlet}}

twiddle.json

{
  "version": "0.11.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.10.2",
    "ember-data": "2.11.0",
    "ember-template-compiler": "2.10.2",
    "ember-testing": "2.10.2"
  },
  "addons": {}
}