Get model index inside ActiveDataProvider, Yii2

I try to get my model position inside dataProvider. I have a listview with pager:

 Pjax::begin();
                echo ListView::widget([
                    'dataProvider' => $dataProvider,
                    'itemOptions' => ['class' => 'item'],
                    'itemView' => 'tree_part',

                    'pager' => [
                        'class' => ScrollPager::className(),
                         'enabledExtensions'=> [ScrollPager::EXTENSION_SPINNER],
                          'spinnerSrc'=> Yii::$app->request->baseUrl.'/images/spinner.gif',
                        ]
               ]);
Pjax::end();

I know i can access$model, $widget, $index in my partial view tree_part.php, but I cannot figure out how to get current $model index inside the data.

My dataprovider:

 $dataProvider = new ActiveDataProvider([ 
        'query' => $query, 
        'sort'=> ['defaultOrder' => ['creation_date'=>SORT_DESC]],
        'pagination' => [
            'pageSize' => 12,
        ],
    ]); 

So if thepagesize is 12, $index variable will only show the value of 0-11. What I need is to get "global" index out of the total count of models.

Any advise would be highly appreciated.