talent_map/server/common/modules/book/frontend/views/default/_layout.php

<?php
/**
 * Created by PhpStorm.
 * User:  NODELOG
 * Date: 2016/12/15
 * Time: 下午3:14
 */

/**
 * @var \yii\web\View $this
 * @var common\modules\book\models\Book $book
 */
use common\helpers\Tree;

$chapters = $book->chapters;
$items = [];
foreach ($chapters as $chapter) {
    $item = [];
    $item['label'] = $chapter->chapter_name;
    $item['url'] = empty($chapter->chapter_body) ? '#' : ['chapter', 'id' => $chapter->id];
    $item['active'] = request('id') == $chapter->id && Yii::$app->controller->action->id == 'chapter';
    $item['id'] = $chapter->id;
    $item['pid'] = $chapter->pid;
    $items[] = $item;
}
$menuItems = Tree::build($items, 'id', 'pid', 'items');
?>
<div class="row">
    <div class="col-md-3">
        <?= \common\widgets\SideNavWidget::widget([
            'items' => $menuItems
        ]) ?>
    </div>
    <div class="col-md-9">
        <?= $content ?>
    </div>
</div>