Option Explicit
 
Private Declare Function SendMessage Lib "user32" _
 Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, _
 ByVal wParam As Long, lParam As Any) As Long
Public Declare Function OleTranslateColor Lib "oleaut32.dll" _
 (ByVal lOleColor As Long, ByVal lHPalette As Long, _
 ByRef lColorRef As Long) As Long
 
Private Const TVM_SETBKCOLOR = 4381&
 
Public Sub TreeViewBackColor(tvw As TreeView, _
 Optional ByVal BackColor As OLE_COLOR = vbWindowBackground, _
 Optional ByVal NodesBackColor As Boolean = True)
 
  Dim nNode As Node
  Dim nIL As ImageList
  Dim nBackColor As Long
  Dim nStyle As Long
 
  With tvw
    Set nIL = tvw.ImageList
    If Not (nIL Is Nothing) Then
      nIL.BackColor = BackColor
    End If
    nStyle = .Style
    OleTranslateColor BackColor, 0&, nBackColor
    SendMessage .hwnd, TVM_SETBKCOLOR, 0, ByVal nBackColor
    .Style = 0
    .Style = nStyle
    If NodesBackColor Then
      For Each nNode In .Nodes
         nNode.BackColor = BackColor
      Next nNode
    End If
  End With
End Sub