title: Class 'yii\jui\DatePicker' not found (Not a duplicate one)!
body: <p>I used composer to install it. I checked all needed files in vendor/yiisoft/yii2-jui existing. The extensions.php is all right. I have "use yii\jui\DatePicker;" in my file, But it still doesn't work.
  How can I fix it? Thanks.</p>