Better AR with Yii - 2

Foo.php

<?php
class Foo extends CActiveRecord {
    public function newestFirst()
    {
        $this->dbCriteria->order = 'created_on DESC';
        return $this;
    }
}

FooController.php

<?php
class FooController extends Controller {
    public function actionIndex()
    {
        $this->render('index',array(
            'dataProvider' => new CActiveDataProvider(
                Foo::model()->newestFirst()
            ),
        ));
    }
}