Yii2 dropdown

Yii2 dropdown.php

<?php

    [
        'attribute' => 'foo',
        'value' => 'foo',
        'label' => Yii::t('adminpanel', 'Foo'),
        'filter' => Foo::getFooList(),
        'filterType' => GridView::FILTER_SELECT2,
        'filterOptions' => ['style' => 'min-width: 85px'],
        'filterWidgetOptions' => [
            'options' => ['prompt' => ''],
            'pluginOptions' => [
                'allowClear' => true,
                'width' => 85,
            ],
        ],
    ],