New Twiddle

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  actions: {
    setFoo(item) {
      item.set('foo', 'Bazinga')
    }
  },
  
  init() {
    console.log('aaaa')
    this.items = []
    
    for(let i = 0; i < 5; i++) {
      this.items.pushObject(    this.store.createRecord('test',  { firstName: 'Name' + i}))
    }
 },
  });

models.test.js

import DS from 'ember-data';

export default DS.Model.extend({
  firstName: DS.attr('string')
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
{{#each items as  |item|}}
   |{{item.firstName}}|{{item.foo}}|
<button class="text-center" onclick={{action 'setFoo' item}}>Set</button>
<hr>
{{/each}}

twiddle.json

{
  "version": "0.7.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.3/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.4.3/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.3/ember-template-compiler.js"
  }
}