Object depth

controllers.application\.js

import Controller from '@ember/controller';
import { inject as service } from '@ember/service';
import { action } from '@ember/object';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle'
  @service objectDepth
  @action updateService() {
    this.objectDepth.set('rootItem', 'newValue')
  }
}

services.object-depth\.js

import Service from '@ember/service';
import { tracked } from '@glimmer/tracking';

export default class ShoppingCartService extends Service {
  @tracked rootItem = 'rootItem'

  get subObject1() {
    return {
    subItem: this.rootItem
    }
  }
  subObject2 = {
    subItem: 'y'
  }
}

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
<p>From root: {{this.objectDepth.rootItem}}</p>
<p>From sub1: {{this.objectDepth.subObject1.subItem}}</p>
<p>From sub2: {{this.objectDepth.subObject2.subItem}}</p>
<p><button {{on 'click' this.updateService}}>Update</button></p>
<br>
<br>

twiddle\.json

{
  "version": "0.17.0",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.17.0",
    "ember-template-compiler": "3.17.0",
    "ember-testing": "3.17.0"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}