Info.TV_HITTESTINFO

If OpenWindow(0, 0, 0, 355, 180, #PB_Window_SystemMenu|#PB_Window_ScreenCentered, "TreeGadget")
  
  If CreateGadgetList(WindowID(0))
    TreeGadget(0, 10, 10, 160, 160)                         ; TreeGadget standard
    For a = 0 To 10
      AddGadgetItem(ID, - 1, "Normal Item " + Str(a))    ; if you want to add an image, use
      AddGadgetItem(ID, - 1, "Node " + Str(a))           ; UseImage(x) as 4th parameter
      OpenTreeGadgetNode(ID)
      AddGadgetItem(ID, - 1, "Sub-Item 1")
      AddGadgetItem(ID, - 1, "Sub-Item 2")
      AddGadgetItem(ID, - 1, "Sub-Item 3")
      AddGadgetItem(ID, - 1, "Sub-Item 4")
      CloseTreeGadgetNode(ID)
      AddGadgetItem(ID, - 1, "File " + Str(a))
    Next
  EndIf
  
  Repeat
    Select WaitWindowEvent()
      Case #PB_EventGadget
        
        Select EventGadgetID()
          
          Case 0
            If EventType() = #PB_EventType_LeftClick
              
              GetCursorPos_(@Pos.POINT)
              ScreenToClient_(GadgetID(0), @Pos.POINT)
              
              Info\pt\x = Pos\x : Info\pt\y = Pos\y
              SendMessage_(GadgetID(0), #TVM_HITTEST, 0, @Info)
              
              If Info\flags & #TVHT_ONITEMBUTTON
                SendMessage_(GadgetID(0), #TVM_SELECTITEM, #TVGN_CARET, Info\hItem)
                Debug "L'élément " + Str(GetGadgetState(0))+" a été selectionné"
              EndIf
              
              If GetGadgetItemState(0, GetGadgetState(0)) &#PB_Tree_Expanded
                Debug "la branche est ouverte"
              ElseIf GetGadgetItemState(0, GetGadgetState(0)) &#PB_Tree_Collapsed
                Debug "la branche est fermée"
              EndIf
            EndIf
            
        EndSelect
      Case #PB_EventCloseWindow
        Quit = #True
    EndSelect
  Until Quit
EndIf