accessing models across sibling routes

controllers.application.js

import Ember from 'ember';

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

router.js

import Ember from 'ember';
import config from './config/environment';

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

Router.map(function() {
  this.route('first');
  this.route('second');
});

export default Router;

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  
});

routes.first.js

import Ember from 'ember';

export default Ember.Route.extend({
  sharingService: Ember.inject.service(),
  
  model() {
   return {
		numbers: this.get('sharingService').numbersData,   
    fruit: this.get('sharingService').fruitData
   }
  },
  
  actions: {
   showServiceData() {
   	alert(JSON.stringify(this.get('sharingService').fruitData))
   },
    
   checkStore() {
   	sharingService.getStore();
   }
  }
});

routes.index.js

import Ember from 'ember';

export default Ember.Route.extend({
  sharingService: Ember.inject.service(),
  
  // All array data must be in the form of an Ember Object in order to immediately pass changes to the service
  fruitData: [Ember.Object.create({name: 'pear'}), Ember.Object.create({name: 'orange'}), Ember.Object.create({name: 'apple'})],
  numberData: [Ember.Object.create({name: '1'}), Ember.Object.create({name: '2'}), Ember.Object.create({name: '3'})],
  model() {
    // If you were getting the data from an Ajax call, you could set the service
    // data in a "then" promise
    this.get('sharingService').set('fruitData', this.get('fruitData')),
    this.get('sharingService').set('numbersData', this.get('numberData')) 
    
  	return this.get('sharingService');
  },
  afterModel: function() {
  	this.transitionTo('first');
  }
});

routes.second.js

import Ember from 'ember';

export default Ember.Route.extend({
  sharingService: Ember.inject.service(),
  
  model() { 
    debugger;
  	return {
      fruitData: this.get('sharingService').fruitData 
    }
  }
});

services.sharing-service.js

import Ember from 'ember';

export default Ember.Service.extend({
  store: Ember.inject.service(),
  numbersData: undefined,
  fruitData: undefined,
  
  getStore() {
  	debugger;
  }

});

styles.app.css

body {
  margin: 12px 16px;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
{{link-to 'First Route' 'first'}}
{{link-to 'Second Route' 'second'}}
<br>
<br>
{{outlet}}
<br>
<br>

templates.first.hbs

{{log model}}

<h4>Changing these values, immediately propogates to the second route</h4>
<h2>First Route</h2>
{{#each model.fruit as |fruit|}}
<li>{{input value=fruit.name}}</li>
{{/each}}

<h2>There are {{model.fruit.length}} fruits left</h2>

<button {{action 'showServiceData'}}>Service Data</button>

<button {{action 'checkStore'}}>Check Store in Service</button>

templates.second.hbs

<h2>Second Route</h2>

<h4>... and vice versa</h4>

{{#each model.fruitData as |fruit|}}
<li>{{input value=fruit.name}}</li>
{{/each}}

twiddle.json

{
  "version": "0.10.4",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.7.0",
    "ember-data": "2.7.0",
    "ember-template-compiler": "2.7.0"
  },
  "addons": {}
}