EnableExplicit

Define EventID
Define a

If OpenWindow(0,0,0,500,400,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered)
  TrackBarGadget(1,10,10,200,50,0,100,0)
  
  For a=0 To 100 Step 20
    SendMessage_(GadgetID(1),#TBM_SETTIC,0,a)
  Next
  
  Repeat
    EventID=WaitWindowEvent()
    If EventID = #PB_Event_CloseWindow
      End
    EndIf
  ForEver
EndIf