I am trying to pass a list to a Popup Editor, but it is not possible. Is there a workaround for this? 
In more detail there is a list of records containing a multiple selection mechanism (using checkboxes). After selecting one or more row s, the action associated and possible for that/those selections appears inside a combobox along with an OK button (see image) - that has currently an onClick Action that what it does is check if the checkboxes are 'true' and inserting the ones that are in a list that is local.

What I need  now is that when I click that button in shows me a confirmation popup and this popup contains the list of selected items (that i previously saved on a list). 

I can't query the database for this because I am not saving this checked state in it. Is it possible to do it any other way?

Thanks for the help in advance

Try a session variable