How to implement a draggable ExtendedOverlayItem on OSMDroid?

I'm developing a feature to drag a map overlay (using ExtendedOverlayItem class), using osmdroid and OSMBonusPack.

This question talks about a possible solution:

Unable to implement onTouchEvent (Drag & Drop) with Osmdroid

So, my questions are:

1 - Where do I put that code?

2 - Should I create a new class? extending from which other class?

Additional Similar questions:

How do you implement OverlayItem to be draggable? (Using ItemizedIconOverlays if possible)

confusion between overlay, overlayitem and itemizedoverley