LVSwitch Gui ID

  Will switch the data of the current listview with the one 
  specified. Everything else (IDs, gadget attributes, lvmode 
  etc) will remain the same.

  ex:

  lvuse gui 1         ; use lv No.1
  lvswitch gui 2      ; switch all the data with lv No.2

  This is helpfull when you use LVs as databases, or want to 
  have one visible lv gadget and many lists.