How to make a section show the selected row's information?

I have got an UI with two sections. The first section contains a repeat grid layout. The last one is a section with detailed information about selected grid's row.

I need to provide a feature to select rows using "Up" and "Down" keys (press "Up" - one element above, "Down" - one bellow). And the section with information must be refreshed. I managed to develop a feature of focusing leveraging Up/Down keys. But I have got an interesting bug: the next row is selected, but the section is refreshed and show info about previous row.

Here is an example of the actiion configuration:

The issue is still unresolved.

I struggled to find out an out-of-box solution, but I realized that Pega doesn't provide any.
My bug happens because the section refreshes when the previous element is selected.
And after refreshing it jumps to the next element. I performed many variants and found out that I can't change the order.
The only way to provide this is to code custom handler.