zxcms/backend/components/menu/widgets/views/menu.php

<?php
/**
 * Created by Error202
 * Date: 11.07.2018
 */

/**
 * @var $this \yii\web\View
 * @var $items array
 * @var $menu \core\entities\menu\Menu
 */

use backend\components\menu\assets\MenuAsset;
use yii\helpers\Html;
use yii\helpers\Url;
use yii\web\JsExpression;

MenuAsset::register($this);

function menu_generate($items) {
	$html = '<ol class="dd-list">';
	foreach ($items as $item) {
		$html.=Yii::$app->getView()->render( '_item', [
			'item' => $item,
		] );
	}
	return $html . '</ol>';
}

$url = Url::to(['/menu/save-menu-items']);
$redirect = Url::to(['menu/index', 'id' => $menu->id]);
?>

<div class="dd" id="nestable3">
	<?= menu_generate($items) ?>
</div>

<!--
<div class="dd" id="nestable2">
	<ol class="dd-list">

		<li class="dd-item dd3-item" data-id="13">
			<div class="dd3-content">
				<div class="panel-group" id="accordion">
					<div class="panel panel-default">
						<div class="panel-heading">
							<h4 class="panel-title">
								<div class="dd-handle dd3-handle"> </div>
								<a data-toggle="collapse" data-parent="#accordion" href="#collapse1">Item 13
									<i class="fa fa-angle-down pull-right" aria-hidden="true"></i></a>
							</h4>
						</div>
						<div id="collapse1" class="panel-collapse collapse">
							<div class="panel-body">
								Content Panel
							</div>
						</div>
					</div>
				</div>
			</div>
		</li>


		<li class="dd-item dd3-item" data-id="14">
			<div class="dd3-content">
				<div class="panel-group" id="accordion">
					<div class="panel panel-default">
						<div class="panel-heading">
							<h4 class="panel-title">
								<div class="dd-handle dd3-handle"> </div>
								<a data-toggle="collapse" data-parent="#accordion" href="#collapse2">Item 14
									<i class="fa fa-angle-down pull-right" aria-hidden="true"></i></a>
							</h4>
						</div>
						<div id="collapse2" class="panel-collapse collapse">
							<div class="panel-body">
								Content Panel
							</div>
						</div>
					</div>
				</div>
			</div>
		</li>

		<li class="dd-item dd3-item" data-id="15">
			<div class="dd3-content">
				<div class="panel-group" id="accordion">
					<div class="panel panel-default">
						<div class="panel-heading">
							<h4 class="panel-title">
								<div class="dd-handle dd3-handle"> </div>
								<a data-toggle="collapse" data-parent="#accordion" href="#collapse3">Item 15
									<i class="fa fa-angle-down pull-right" aria-hidden="true"></i></a>
							</h4>
						</div>
						<div id="collapse3" class="panel-collapse collapse">
							<div class="panel-body">
								Content Panel
							</div>
						</div>
					</div>
				</div>
			</div>

			<ol class="dd-list">
				<li class="dd-item dd3-item" data-id="16">
					<div class="dd3-content">
						<div class="panel-group" id="accordion">
							<div class="panel panel-default">
								<div class="panel-heading">
									<h4 class="panel-title">
										<div class="dd-handle dd3-handle"> </div>
										<a data-toggle="collapse" data-parent="#accordion" href="#collapse4">Item 16
											<i class="fa fa-angle-down pull-right" aria-hidden="true"></i></a>
									</h4>
								</div>
								<div id="collapse4" class="panel-collapse collapse">
									<div class="panel-body">
										Content Panel
									</div>
								</div>
							</div>
						</div>
					</div>
				</li>
			</ol>

		</li>




	</ol>
</div>

</div>

<div style="clear: both;"></div>
<hr>

<button class="btn btn-primary" id="serialize">Serialize</button>
<hr>
<textarea class="form-control" id="output"></textarea>

<hr>
<textarea class="form-control" id="output2"></textarea>
-->

	<div style="clear: both;"></div>
	<hr>

<?= Html::button(Yii::t('buttons', 'Save'), [
	'class' => 'btn btn-success pull-right',
	'onclick' => new JsExpression('sendTree('.$menu->id.', "'.$url.'", "'.$redirect.'")'),
]) ?>