Visual Basic

I have been banging my head on this for several days now.  I wanted to have a better looking flat combobox and be able to change the button color.  I also wanted to remove the highlighting that occurs after an item is selected.  What I came up with works, until visual styles is enabled.  When visual styles are enabled, the text in the textbox area of the combobox either gets painted over, or not drawn at all.  I could disable visual styles, but I would rather not have to do that as it just seem like a band-aid to fix an issue that I feel should not be happening.  I tried disabling visual styles using SetWindowTheme, but that does not seem to work.  I was hoping someone out there might notice what I am doing wrong.

Here is the code:

Public Class UMSComboBox : Inherits ComboBox

    Friend Declare Unicode Function SetWindowTheme Lib "UxTheme.dll" _
     (ByVal hwnd As IntPtr, _
     ByVal pszSubAppName As String, _
     ByVal pszSubIdList As String) As Integer

    Public Property ButtonColor() As Color
        Get
            Return _ButtonColor
        End Get
        Set(ByVal Value As Color)
            _ButtonColor = Value
            Me.Invalidate()
        End Set
    End Property
    Private _ButtonColor As Color = SystemColors.Control

    Public Property HighlightColor() As Color
        Get
            Return _HighlightColor
        End Get
        Set(ByVal Value As Color)
            _HighlightColor = Value
            Me.Invalidate()
        End Set
    End Property
    Private _HighlightColor As Color = SystemColors.Highlight

    Public Sub New()
        MyBase.New()
        Me.DrawMode = Windows.Forms.DrawMode.OwnerDrawFixed
        SetStyle(ControlStyles.OptimizedDoubleBuffer, True)
        'SetStyle(ControlStyles.AllPaintingInWmPaint, True)
        SetStyle(ControlStyles.ResizeRedraw, True)
        SetStyle(ControlStyles.Selectable, True)
        SetStyle(ControlStyles.SupportsTransparentBackColor, True)
        SetStyle(ControlStyles.UserPaint, True)
    End Sub


    Protected Overrides Sub OnPaint(e As System.Windows.Forms.PaintEventArgs)

        Dim g As Graphics = e.Graphics
        g.FillRectangle(New SolidBrush(Me.BackColor), Me.ClientRectangle)
        ControlPaint.DrawBorder(g, Me.ClientRectangle, Me.ForeColor, ButtonBorderStyle.Solid)

        'Draw the background of the dropdown button
        Dim rect As Rectangle = New Rectangle(Me.Width - 12, 0, 12, Me.Height)
        g.FillRectangle(New SolidBrush(_ButtonColor), rect)
        ControlPaint.DrawBorder(g, rect, Me.ForeColor, ButtonBorderStyle.Solid)

        'Create the path for the arrow
        Dim pth As Drawing2D.GraphicsPath = New Drawing2D.GraphicsPath()
        Dim TopLeft As PointF = New PointF(Me.Width - 10, CSng((Me.Height - 5) / 2))
        Dim TopRight As PointF = New PointF(Me.Width - 3, CSng((Me.Height - 5) / 2))
        Dim Bottom As PointF = New PointF(Me.Width - 6, CSng((Me.Height + 2) / 2))
        pth.AddLine(TopLeft, TopRight)
        pth.AddLine(TopRight, Bottom)

        g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality

        'Draw the arrow
        g.FillPath(New SolidBrush(Me.ForeColor), pth)
        'If Me.DroppedDown Then
        '    g.FillPath(New SolidBrush(SystemColors.HighlightText), pth)
        'Else
        '    g.FillPath(New SolidBrush(SystemColors.ControlText), pth)
        'End If

    End Sub

    Protected Overrides Sub OnDrawItem(e As System.Windows.Forms.DrawItemEventArgs)
        If e.Index < 0 Then Exit Sub
        Dim rect As Rectangle = e.Bounds
        If Me.DroppedDown Then
            If CBool(e.State And DrawItemState.Selected) Then
                e.Graphics.FillRectangle(New SolidBrush(_HighlightColor), rect) 'change the selected color you like
            Else
                e.Graphics.FillRectangle(New SolidBrush(Me.BackColor), rect)
            End If
        Else
            e.Graphics.FillRectangle(New SolidBrush(Me.BackColor), rect)
        End If
        Dim itemtext As String = Me.Items(e.Index).ToString
        Dim b As New SolidBrush(Me.ForeColor)
        e.Graphics.DrawString(itemtext, e.Font, b, e.Bounds, StringFormat.GenericDefault)
    End Sub

    Protected Overrides Sub OnHandleCreated(e As System.EventArgs)
        MyBase.OnHandleCreated(e)
        Me.FlatStyle = Windows.Forms.FlatStyle.System
        SetWindowTheme(Me.Handle, String.Empty, "COMBOBOX")
    End Sub

End Class

Imports System.Linq.Dynamic
.....
Dim mylist As IQueryable(Of Myobject)
Dim ob1 As New List(Of ObjectParameter)
Dim dynstr as string=string.empty

dynstr += "id= @id"
ob1.Add(New ObjectParameter("id", 26))
mylist=context.MyObjects.Where(dynstr,ob1.ToArray()).Tolist

dynstr+="id=26"