custom element test

controllers.application.js

import Ember from 'ember';
import '../custom-element';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  count: 0,
  actions: {
    handleCounterClick() {
  	  this.incrementProperty('count');
    }
  }
});

custom-element.js

/* javascript things */
eval(`
class ClickCounter extends HTMLElement {
 constructor() {
   super();
   let shadow = this.attachShadow({ mode: 'open' });
   this.setup(shadow);
 }

 handleButtonClick() {
   let event = new CustomEvent('customEventName', {
    bubbles: true,
    cancelable: false
  });

	this.dispatchEvent(event);
 }
 
 setup(shadow) {
   let btn = document.createElement('button');
   btn.addEventListener('click', this.handleButtonClick.bind(this), false, false);
   btn.textContent = 'Submit';
   shadow.appendChild(btn);
 }
}

// Define the new element
customElements.define('click-counter', ClickCounter);
`);

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{count}}
<click-counter onclick={{action 'handleCounterClick'}}></click-counter>
<br>
<br>

twiddle.json

{
  "version": "0.13.1",
  "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"
  }
}