Re-rendering ApplicationView with outlet

Question

Short version of this question: I'm trying to re-render my ApplicationView when a specific event happens (a language change). The ApplicationView only contains a simple outlet, however on re-rendering this outlet remains empty. So, what is the correct approach to re-render an entire page?

Simplified application code (http://jsfiddle.net/6ZQh7/2/):

Ember.Handlebars.registerHelper('t', function() {
    return App.get('language') == 'en' ? 'Hi there!' : 'Hallo!';
});
App = Ember.Application.create({
    language: 'en',
    ApplicationView: Em.View.extend({
        templateName: 'application'
    }),
    TestView: Em.View.extend({
        templateName: 'test'
    }),
    ApplicationController: Em.Controller.extend(),

    Router: Em.Router.extend({
        root: Em.Route.extend({
            toggleLanguage: function(router) {
                App.set('language', App.get('language') == 'en' ? 'nl' : 'en');

                // view.parentView resolves to the ApplicationView
                router.get('applicationController.view.parentView').rerender();
            },
            index: Em.Route.extend({
                route: '/',
                connectOutlets: function(router) {
                    router.get('applicationController').connectOutlet('test')
                }
            })
        })
    })
});

Corresponding HTML:

<script type="text/x-handlebars" data-template-name="application">
    <h1>{{t whatever}}</h1>
    {{outlet}}
</script>
<script type="text/x-handlebars" data-template-name="test">
    <h2>My Test Page</h2>
    <a href="#" {{action toggleLanguage}}>Toggle language.</a>
</script>

Doing some debugging (well, some; a few hours of it), it seems that when the re-render occurs, the ContainerView that renders the outlet doesn't have a context, which means no currentView (which is bound to this context), which means nothing is rendered in the outlet at all. Scratch that, there is a working context; if I call this.get('templateData.keywords.view.context') in ContainerView#init using the debugger, I get the applicationcontroller. Interestingly enough though, this.get('templateData.keywords.view.context.view') (which should return the view for the outlet) returns undefined, whereas `this.get('templateData.keywords.view.context').get('view') does return the view.

Context: I'm trying to write an internationalized Ember.js app, which contains a simple translation helper outputting strings in the currently set language (used in conjunction with Ember-I18n). Currently changing the language requires a reload of the page, as these language strings are unbound (and I would say rightfully so, as language changes are rare and creating bindings to every string on the page sounds like a bad idea). However, I'd like to just re-render instead of reload.

Answer 1

I am kinda giving the basic approach, Create language Objects as in...

App.Languages = {};
App.availableLanguages = Em.A([App.Languages.En, App.Languages.Pirate]);

App.Languages.En = Em.Object.extend({
  languageName: "English",
  appName: "My application Name"
})

App.Languages.Pirate = Em.Object.extend({
  languageName: "Pirate",
  appName: "!!!Zzzz"
})

App.set('language', App.Languages.En);

Handlebars Helper

Em.Handlebars.registerHelper('loc', function(key){
  currentLanguage = Ember.get('language');
  value = currentLanguage.get('key');
  return Ember.String.htmlSafe(value);
})

Usage:

{{loc appName}}

Changing Language: A dropdown on the top of page as in

{{Ember.Select contentBinding=App.availableLanguages optionValuePath="content" optionLabelPath="content.languageName" selectionBinding="App.language"}}

Hence, when a language is changed, thanks to ember binding the value gets updated :)

Answer 2

I solved the exact same problem by adding an observer method to the application view, which listens to changes in the language setting, and if it detects a change, rerenders the view using the rerender() method.

I have a language controller:

FLOW.languageControl = Ember.Object.create({
    dashboardLanguage:null,

    content:[
     Ember.Object.create({label: "English", value: "en"}),
     Ember.Object.create({label: "Dutch", value: "nl"}),
     Ember.Object.create({label: "Spanish", value: "sp"}),
     Ember.Object.create({label: "French", value: "fr"})],

    changeLanguage:function(){
      locale=this.get("dashboardLanguage.value");
      console.log('changing language to ',locale);

      if (locale == "nl") {Ember.STRINGS=Ember.STRINGS_NL;}
      else if (locale == "fr") {Ember.STRINGS=Ember.STRINGS_FR;}
      else if (locale == "sp") {Ember.STRINGS=Ember.STRINGS_SP;}
      else {Ember.STRINGS=Ember.STRINGS_EN;}
    }.observes('dashboardLanguage')
});

with a dropdown in a handlebars file:

<label>Dashboard language: {{view Ember.Select 
  contentBinding="FLOW.languageControl.content" 
  optionLabelPath="content.label" 
  optionValuePath="content.value" 
  selectionBinding="FLOW.languageControl.dashboardLanguage" }}
</label>

And a (simplified) Navigation view, which renders the top navigation:

FLOW.NavigationView = Em.View.extend({
  templateName: 'navigation',
  selectedBinding: 'controller.selected',

  onLanguageChange:function(){
    this.rerender();
  }.observes('FLOW.languageControl.dashboardLanguage'),
});

When the navigationView detects a language change (which was caused by the user selecting a language from the dropbox), the navigationView is rerendered.

You could do the same thing on the Application view, it is just that I only need the navigation view to be rerendered.