so#43493092

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('doctor', function() {
  this.route('visit', {
    path: '/visit/:visit_id'
   }, function() {
    this.route('order');
  });
});
});

export default Router;

routes.doctor.js

import Ember from 'ember';

export default Ember.Route.extend({
  model() {
    return 'this is doctor route';
  }
});

routes.doctor.visit.js

import Ember from 'ember';

export default Ember.Route.extend({
  model(params) {
    return 'this is visit route ' + params.visit_id;
  }
});

routes.doctor.visit.order.js

import Ember from 'ember';

export default Ember.Route.extend({
  model() {
    return 'this is order route';
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{#link-to 'doctor.visit.order' 1}}Link for visit with id 1{{/link-to}}
<br>
{{#link-to 'doctor.visit.order' 2}}Link for visit with id 2{{/link-to}}
<br>
{{outlet}}
<br>
<br>

templates.doctor.hbs

{{model}}
<br>
{{outlet}}

templates.doctor.visit.hbs

{{model}}
<br>
{{outlet}}

templates.doctor.visit.order.hbs

{{model}}

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}