php composer.phar require --prefer-dist yii-dream-team/yii2-jstree "*"

<?= \yiidreamteam\jstree\JsTree::widget([
    'containerOptions' => [
        'class' => 'data-tree',
    ],
    'jsOptions' => [
        'core' => [
            'multiple' => false,
            'data' => [
                'url' => \yii\helpers\Url::to(['ajax/tree']),
            ],
            'themes' => [
                'name' => 'foobar',
                'url' => "/themes/foobar/js/jstree3/style.css",
                'dots' => true,
                'icons' => false,
            ]
        ],
    ]
]) ?>