Selected select on default ember js - ember.js

Question

I have a model Currencies. Fields in the model are name:string and default:boolean.
On the backend only one of records in database can have default:true. I want it to be selected by default in select in Ember js.
Please give me an example how to make such select and use it
Example:
name: type1 default: false
name: type2 default: true
name: type3 default: false
I want to generate such select :
<selected>
<option>type1</option
<option selected=selected>type2</option
<option>type3</option
</selected>
Route.js
#route 'addincome', { path: 'operations/addincome' }
EmberMoney.AddincomeRoute = Ember.Route.extend
model: ->
EmberMoney.IncomeOperation.createRecord()
setupController: (controller, model) ->
controller.set('currencies', EmberMoney.Currency.find())
controller.set('content', model)
addincome.handlebars
// Some output with Incomes records
{{view EmberMoney.Select viewName="select"
contentBinding="controller.currencies"
optionLabelPath="content.name"
optionValuePath="content.id"
selectionBinding="controller.defaultType"}}
addincome_controller.js
EmberMoney.AddincomeController = Ember.ObjectController.extend({
setDefaultCurrency: function(){
if(this.get('currencies.isLoaded')){
this.set('defaultType', this.get('currencies').findProperty('default'));
}
}.observes('currencies.isLoaded')
})

Answer 1

My answer builds upon that one already posted. The answer is to use the selectionBinding and a clever way to set it up:
{{view Ember.Select
contentBinding="controller.types"
optionLabelPath="content.name"
optionValuePath="content.id"
selectionBinding="controller.selectedCurrency"
}}
EmberMoney.IncomesController = Ember.ArrayController.extend({
selectedCurrency : null,
currenciesObserver: function(){
var currencies = this.get("currencies");
var default = currencies.findProperty("default");
if(default)
this.set("selectedCurrency", default);
}.observes('currencies.#each')
});
How does the solution work?
We set up a selectionBinding (two way) between the Select control and your controller. If you set a currency in your controller in the property 'selectedCurrency', it will be the selected value in the Select control. Vice versa if you select a currency in the Select Box, it will be set in your controller.
I am doing the initial setup with the helper of an observer. The observer is called each time the watched currencies array changes.
Every time it is called, it tries to find a default currency. If it finds one, it sets it in your selectedCurrency property. Now the selectionBinding kicks and does its magic for you.
An additional advantage of this solution is, that you can grab the selected value easily from the property, if the user chooses another currency.

Answer 2

Use selectionBinding for the selection, and ComputedProperty to find the appropriate item
Update
EmberMoney.AddincomeController = Ember.ObjectController.extend({
setDefaultCurrency: function(){
if(this.get('currencies.isLoaded')){
this.set('defaultType', this.get('currencies').findProperty('default'));
}
}.observes('currencies.isLoaded')
})
The advantage of using isLoaded over #each for the observer is that the observer wont get fired everytime a currency is added instead it makes sure to set the value once the entire collection is loaded, Again it is upto the use case to determine which to use when
Details about findProperty
Hope this helps
Screenshot