How to routeName

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  ui: Ember.inject.service(),
  appName: 'Ember Twiddle',
  
  routeNameChanged: Ember.observer('currentRouteName', function () {
  	var name = this.get('currentRouteName');
    this.set('ui.currentRouteName', name);
  })
});

controllers.index.js

import Ember from 'ember';

export default Ember.Controller.extend({
  ui: Ember.inject.service()
});

router.js

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

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

Router.map(function() {
  this.route('foo');
  this.route('bar');
});

export default Router;

services.ui.js

import Ember from 'ember';

export default Ember.Service.extend({
  wittyRouteTitle: Ember.computed('currentRouteName', function() {
    switch (this.get('currentRouteName')) {
      case 'index': return 'My index route';
      case 'foo': return 'The famous foo route';
      case 'bar': return 'Bar anyone?';
      default: return 'How do I populate this property?';
    }
  })
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<p>The ui service says the route is: <em>{{ui.currentRouteName}}</em></p>
<hr>
{{outlet}}

templates.bar.hbs

<p>This is the <strong>bar</strong> route</p>
{{#link-to "foo" tagName="button"}}Goto back to  foo{{/link-to}}
{{#link-to "index" tagName="button"}}Loop back to index{{/link-to}}

templates.foo.hbs

<p>This is the <strong>foo</strong> route</p>
{{#link-to "index" tagName="button"}}Goto back to  index{{/link-to}}
{{#link-to "bar" tagName="button"}}Goto bar{{/link-to}}

templates.index.hbs

<p>This is the <strong>{{ui.currentRouteName}}</strong> route</p>
{{#link-to "bar" tagName="button"}}Goto bar{{/link-to}}
{{#link-to "foo" tagName="button"}}Goto foo{{/link-to}}

twiddle.json

{
  "version": "0.8.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.5.1",
    "ember-data": "2.5.2",
    "ember-template-compiler": "2.5.1"
  }
}