标签浮动在 yii2 中不起作用

问：

我在 Yii2 Basic 中创建了一个表单，并使用 Material Design 来启用浮动标签，但当我点击输入字段时，它的标签不会浮动在上面。这是我的表单代码。

    <?php
    $form = ActiveForm::begin([
                'action' => ['index'],
                'method' => 'get',
    ]);
    ?>


    <div class="panel-body container-fluid">

        <div class="row">
            <div class="col-md-12">
                <div class="col-xs-6 col-lg-6">

                    <div class="form-group form-material floating" data-plugin="formMaterial">
                        <?= $form->field($model, 'corporation_name',[  'labelOptions' => [ 'class' => 'floating-label' ]])->textInput(['maxlength' => true, 'class' => 'form-control'])->label('Corporation Name') ?>    
                    </div>

                    <div class="form-group form-material floating" data-plugin="formMaterial">
                        <?= $form->field($model, 'user_first_name',[  'labelOptions' => [ 'class' => 'floating-label' ]])->textinput(['class' => 'form-control'])->label('Corporation Admin'); ?>
                    </div>
                </div>
                <div class="col-xs-6 col-lg-6">
                    <div class="form-group form-material floating" data-plugin="formMaterial">
                        <div class="example"> <b role="presentation"></b>
                            <?= $form->field($model, 'corporation_status')->dropDownList(Yii::$app->appstatues->status, ['prompt' => 'Status'])->label(false); ?>
                        </div>
                    </div>
                </div>
            </div>
            <div class="col-md-12">
                <div class="form-group form-material floating m-t-27" data-plugin="formMaterial">
                    <?= Html::submitButton('Search', ['class' => 'btn-primary btn waves-effect waves-light   waves-effect']) ?>
                    <?= Html::resetButton('Reset', ['class' => 'btn-primary btn waves-effect waves-light   waves-effect', 'onclick' => 'location.href = "/admin/corporations";']) ?>

                </div>
            </div>
        </div>

    </div>
    <?php ActiveForm::end(); ?>

</div>

谁能看出我做错了什么？