If OpenWindow(0,0,0,500,250,"Window",#PB_Window_SystemMenu|#PB_Window_ScreenCentered)
  ButtonGadget(1,10,10,100,20,"Menü wechseln",0)
  
  If CreateMenu(1,WindowID(0))
    MenuTitle("Datei")
      MenuItem(1,"Eintrag",0)
  EndIf
  
  If CreateMenu(2,WindowID(0))
    MenuTitle("File")
      MenuItem(1,"Item",0)
  EndIf
  
Repeat
EventID=WaitWindowEvent()
If EventID=#PB_Event_Gadget
  Select EventGadget()
    Case 1
      If Menustate=0
        SetMenu_(WindowID(0),MenuID(1))
        Menustate=1
      Else
        SetMenu_(WindowID(0),MenuID(2))
        Menustate=0
      EndIf
  EndSelect
EndIf
If EventID=#PB_Event_CloseWindow
  Quit=1
EndIf
Until Quit=1
EndIf