Penggunaan yii2-upload-file

upload.php

<?php
// class User
class User extends ActiveRecord
{
    ...
    public function behaviors()
    {
        return [
            [
                'class' => 'mdm\upload\UploadBehavior',
                'savedAttribute' => 'avatar_id', // <- untuk nyimpan id file
            ],
        ];
    }
}

?>
// Cara mengakses avatar
<?= Yii::$app->user->identity->username ?>
<?= Html::img(['/file', 'id' => $model->Yii::$app->user->identity->avatar_id]) ?>