Module controllers navigation pills (Phundament 4)

_nav.php

    <ul class="nav nav-pills">
        <?php
        foreach (\Yii::$app->getModule('admin')->getControllers($this->context->module->id) AS $i => $controller):
            ?>
            <li role="presentation">
                <?= yii\helpers\Html::a(
                    $controller,
                    ["/{$this->context->module->id}/$controller"],
                    ['class' => 'btn btn-default btn-flat']
                ); ?>
            </li>
        <?php endforeach; ?>
    </ul>