ember-loading-example

controllers.application.js

import Ember from 'ember';

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

router.js

import EmberRouter from '@ember/routing/router';
import config from './config/environment';

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

Router.map(function() {
  this.route('my-route',{path:'/my-route'});
});

export default Router;

routes.my-route.js

import { Promise as EmberPromise } from 'rsvp';
import Ember from 'ember';

export default Ember.Route.extend({
  model(params) {
    let promise = new EmberPromise(function(resolve) {
      setTimeout(() => {
        resolve("my model result");
      }, 2000);
    });
    return promise;
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
{{link-to "go to my-route" "my-route" }}
<br>
{{outlet}}
<br>
<br>

templates.loading.hbs

...Template is loading please wait...
<img src="https://upload.wikimedia.org/wikipedia/commons/b/b1/Loading_icon.gif" />

templates.my-route.hbs

model result: {{model}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}