Default drag & drop operation

By default, all DISPLAY ARRAY dialogs implement a default drag operation that copies all selected rows to the drag & drop buffer as a tab-separated list of values, as if you would implement:

DEFINE dnd ui.DragDrop 
...
DISPLAY ARRAY arr TO sr.* ...
...
  ON DRAG_START(dnd)
    CALL dnd.setOperation("copy")
    CALL dnd.setMimeType("text/plain")
    CALL dnd.setBuffer(DIALOG.selectionToString("sr"))
...
END DISPLAY