How to display related documents on Modx Revo?

Question

MODX

Good day. There was such a question.
Let's say there is a page with a certain make and model of a car, how can you make it so that the manager himself selects related documents from the admin panel that fit the topic of this page and display them. What would he mark them with checkboxes or select from a multiple list.

Answer 1

For example, create a multiple choice TV with a possible value @SELECT `pagetitle`,`id` FROM `modx_site_content` WHERE `template` = 'id of the desired template',
output parameters = 'separator'
value = ','
and then substitute the value in getProducts not forgetting &parents=`-1`