ajax octobercms passing value of id

 <button
            type="button"
            class="btn btn-small btn-danger icon-trash"
            data-request="onDeleteItem"
            data-control="popup"
            data-request-data="id: " <<<<<<<----
            data-trigger-action="enable"
            data-stripe-load-indicator>
</button>

// in Configurations.php::controller

public function onDeleteItem()

//question

how do i get the value of id in a list?

scenario: list of all configs in a table, have an custom column, Edit, Delete

i want to click delete, then it will delete the item, but how do i get the ID?