how to sort values from database using Select2-widget in yii2

Question

how sorting values from database using Select2-widget from kartik in framework yii2? Try like this, but nothing is sorting as well as no error, neither in php nor in Js.:

     [
        'attribute' => 'id_rubrik',
        'value' => function($model) {
            return $model->rubrik->bez;
        },
        'filterType' => GridView::FILTER_SELECT2,
        'filter' => \yii\helpers\ArrayHelper::map(\backend\models\LRubrik::find()->orderBy('bez DESC')->asArray()->all(), 'id', 'bez'),
        'filterWidgetOptions' => [
            'pluginOptions' => ['allowClear' => true],
        ],
        'filterInputOptions' => ['placeholder' => 'Bitte wählen..', 'id' => 'grid-ds-substanz-search-id_rubrik']
    ],