用戶繪製TabControl上的Aero效果

在我的應用程序中，我希望我的tabcontrol在標題上具有aero效果。這適用於正常的WinForms TabControl的使用此代碼：用戶繪製TabControl上的Aero效果

Imports System.Runtime.InteropServices 

    <DllImport("dwmapi.dll")> _ 
    Private Shared Function DwmExtendFrameIntoClientArea(ByVal hwnd As IntPtr, ByRef pMarInset As MARGINS) As Integer 
    End Function 

<StructLayout(LayoutKind.Sequential)> _ 
Private Structure MARGINS 
    Public cxLeftWidth As Integer 
    Public cxRightWidth As Integer 
    Public cyTopHeight As Integer 
    Public cyBottomHeight As Integer 
End Structure

問題是，我有一個自定義的TabControl類（與實際要大得多，並且具有更爲複雜的OnPaint（）重寫比下文）

Public Class CustomTab 
    Inherits TabControl 

    Public Sub New() 
     SetStyle(ControlStyles.UserPaint or ControlStyles.ResizeRedraw,True) 
    End Sub 

    Protected Overrides Sub OnPaint(e as PaintEventArgs) 
     Dim g as Graphics = e.Graphics 
     Dim r as Rectangle 

     For i=0 to TabCount - 1 
      If i = SelectedIndex 
       r = GetTabRect(i) 
       g.FillRectangle(New SolidBrush(My.Settings.TabColor),r) 
      Else 
       r = GetTabRect(i) 
       g.FillRectangle(New SolidBrush(SystemColors.Control),r) 
      End If 
     Next 
    End Sub 
End Class

當我嘗試使用這個玻璃效果時，它不會像正常一樣顯示在標題中。有誰知道爲什麼Userdrawn tabcontrol沒有透明頭文件？

工作（普通的TabControl）： enter image description here