Updating fixtures? - ember.js

Question

I'm following the official Ember guide to do a Todo app.
Is it possible to do a persistent change to the fixtures? If so, how? Because with the code I have, clicking the check box doesn't save the value persistently to the fixtures.
index.html:
<script type="text/x-handlebars" data-template-name="todos">
<ul id="todo-list">
{{#each itemController="todo"}}
<li {{bind-attr class="isCompleted:completed"}}>
{{input type="checkbox" checked=isCompleted class="toggle"}}
<label>{{title}}</label><button class="destroy"></button>
</li>
{{/each}}
</ul>
</script>
application.js:
window.Todos = Ember.Application.create();
Todos.ApplicationAdapter = DS.FixtureAdapter.extend();
models/todo.js:
Todos.Todo = DS.Model.extend({
title: DS.attr('string'),
isCompleted: DS.attr('boolean')
});
Todos.Todo.FIXTURES = [
{
id: 1,
title: 'Learn Ember.js',
isCompleted: true
}
];
controllers/todo_controller.js:
Todos.TodoController = Ember.ObjectController.extend({
isCompleted: function(key, value){
var model = this.get('model');
if (value === undefined) {
// property being used as a getter
return model.get('isCompleted');
} else {
// property being used as a setter
model.set('isCompleted', value);
model.save();
return value;
}
}.property('model.isCompleted')
});

Answer 1

I don't believe so. At the end of that tutorial, there's a section for replacing the fixture adapter with local storage so that you get real persistence. http://emberjs.com/guides/getting-started/using-other-adapters/
js/application.js
window.Todos = Ember.Application.create();
Todos.ApplicationAdapter = DS.LSAdapter.extend({
namespace: 'todos-emberjs'
});
index.html
<!--- ... additional lines truncated for brevity ... -->
<script src="js/libs/ember-data.js"></script>
<script src="js/libs/localstorage_adapter.js"></script>
<script src="js/application.js"></script>
<!--- ... additional lines truncated for brevity ... -->