Yii2-如何使用下拉列表隐藏和显示Div类

Question

我有如下所示的表格

当学习中心的下拉列表处于打开状态时，如果未选择任何值，则搜索条件应隐藏。但是当选择一个值时，应该显示。搜索条件默认情况下应隐藏。

控制器

public function actionIndex()
{
    $model = new Programme();       
    $model->scenario = 'import-programme';

    return $this->render('index', [
        'model' => $model,
    ]);
}

查看

<?php $form = ActiveForm::begin([
'id' => 'import-programme',
'enableAjaxValidation' => false,
'options' => ['enctype' => 'multipart/form-data'],
]); ?>

<div class="box-info box box-solid view-item col-xs-12 col-lg-12 no-padding">
<div class="box-header with-border">
<h3 class="box-title"><i class="fa fa-search"></i> <?php echo Yii::t('app', 'Select Criteria'); ?></h3>
</div>
<div class="box-body no-padding">


    <div class="col-xs-12 col-sm-6 col-lg-6">
        <?= $form->field($model, 'state_office_id')->widget(Select2::classname(), [
            'data' => ArrayHelper::map(\common\models\StateOffice::find()->where(['is_status' => 0])->all(),'id','state_name'),
            'language' => 'en',
            'options' => ['placeholder' => '--- Select State Office ---', 
                'onchange'=>'
                    $.get( "'.Url::toRoute('dependent/getstudycentre').'", { id: $(this).val() } )
                        .done(function( data ) {
                            $( "#'.Html::getInputId($model, 'study_centre_id').'" ).html( data );
                        }
                    );' 
            ],
         //   'disabled'=>'true',
            'pluginOptions' => [
                'allowClear' => true
            ],
        ]); ?>                            

    </div>
    <div class="col-xs-12 col-sm-6 col-lg-6">
        <?= $form->field($model, 'study_centre_id')->widget(Select2::classname(), [
        'data' => ArrayHelper::map(\common\models\StudyCentre::findAll(['state_office_id' => $model->state_office_id]),'id','study_centre_name'),
            'language' => 'en',
            'options' => ['placeholder' => '--- Select Study Centre ---'],
            'pluginOptions' => [
                'allowClear' => true
            ],
        ]); ?>                              
    </div>         
</div>