EnableExplicit

Define a

If OpenWindow(0,0,0,500,250,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered)
  PanelGadget(1,10,10,480,230)
    For a=1 To 5
      AddGadgetItem(1,-1,"Paneltab "+Str(a),0,0)
    Next
  CloseGadgetList()
  SetGadgetState(1,2)
  
  MessageRequester("","Ausgewählter Reiter: "+Str(SendMessage_(GadgetID(1),#TCM_GETCURSEL,0,0)),0)
Repeat : Until WaitWindowEvent() = #PB_Event_CloseWindow
EndIf