omg-loading

application.controller.js

import Ember from 'ember';

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

application.template.hbs

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

{{omg-loading}}
<br>
<br>

omg-loading.component.js

import Ember from 'ember';

const { get, set } = Ember;

let callback = function(fun) {
  // addon is working
  //fun();
};

export default Ember.Component.extend({
  loaded: false,
  init() {
    this._super(...arguments);
  	callback(() => this.set('loaded', true) );
  }
});

omg-loading.template.hbs

{{yield}}
{{#if loaded}}
<h1>I am ready to rock</h1>
{{/if}}

<button disabled={{unless loaded 'disabled'}}>Click Me</button>

twiddle.json

{
  "version": "0.6.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.3.1/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.3.3/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember-template-compiler.js"
  }
}