yii2 GridView 分类筛选给默认值 prompt

<?= GridView::widget([
    'dataProvider' => $dataProvider,
    'filterModel' => $searchModel,
    'columns' => [
        'id',
        ['attribute'=>'cid',
            'value'=>function($model){
                return $model->C->name;
            },
            'filter' => \app\models\Category::get_one_all_category('article'),
　　　　　　　　//  给下拉框加默认值
            'filterInputOptions' => ['prompt'=>'全部','class'=>'form-control'],
        ],
        'name',
        ['class' => 'yii\grid\ActionColumn'],
    ],
]); ?>