How to set a list of values ​​for a listbox in MODX?

Question

MODX

Standard json "form tabs"

[
{
    "caption":"Test",
    "fields":[
        {
            "field":"cat",
            "caption":"cat",
            "inputTVtype": "listbox-multiple",
            "inputTV": "category"
        }
    ]
}
]

Is there any way to make the list of values ​​for the listbox come from another migx field?
The logic is as follows:
- create TV categories - add categories, there are 1, 2 and 3.
- create TV services - fields: Name, Price and Category.
I want the Category field to be generated automatically from the categories TV field as a multiple choice list.
In the admin.
How?

Answer 1

Here 's one way to implement