How data choice is working in Power BI?

Hello everyone,

I am creating custom visual, and in one of the tutorials to create bar chart, I saw that when there are bar chart visual and custom visual, if user chooses column in Power BI visual, appropriate column also become selected. How does it works? Because I have problem with this. I created visual with rectangles and text over these rectangles, and when I use table visual of Power BI for same data, I want to specific rectangle to be selected, with appropriate text of course. How it can be done? 

upd: When I choose data from table, in my custom visual one rectangle is shown, however, there are no text on it.