FNCListBox Mousedown

I'm trying to implement a drag and drop from one list box to another.

The OnMouseDown and OnMouseUp events don't appear to be coming through to my program.  Is there a trick to getting these events working ? 

The project is FMX with Rio.  FMX.TMSFNCListBox  version is



Drag & Drop can be enabled via the Interaction.DragDropMode property. There is no need to implement this manually.

Thanks. I hadn't found that property.