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Owner-Drawn Colored ListBox

I'm trying to develop an Owner-Drawn ListBox and here is what i did :

I'm trying to apply a new property called "AlternatingItemsCellStyle", like the one in the DataGridView Control , but i have some problems implementing it.
I have some classes like "ListBoxCellStyle" which have some properties like -- forecolor, backcolor, selectionforecolor, selectionbackcolor and font property.
i also implement a type converter for that cellstyle and a custom item to be added to the listbox
but that code doesn't work when i added some items to the list nothing changed.
I attached a test form to test that list but , every time i'm trying to run the form i get a strange error messagsays 'Assembly 'C:\Documents and Settings\~~~\Desktop\~~~\~~~\obj\Debug\~~~~.dll' doesn't contain any UserControl types.'


<ToolboxBitmap(GetType(ListBox))> _
<DefaultProperty("AlternatingItemsCellStyle")> _
<DefaultEvent("SelectedIndexChanged")> _
Public Class ColoredListBox
    Inherits ListBox
    Private _DrawMode As DrawMode = Windows.Forms.DrawMode.OwnerDrawVariable
    <DefaultValue(GetType(DrawMode), "OwnerDrawVariable")> _
    Public Overloads Property DrawMode() As DrawMode
            Return _DrawMode
        End Get
        Set(ByVal Value As DrawMode)
            _DrawMode = Value
        End Set
    End Property
    Private _AlternatingItemsCellStyle As ListBoxCellStyle = New ListBoxCellStyle
    '<DefaultValue(GetType(ListBoxCellStyle), "(White), (Black), (Maroon), (255, 224, 192), (Tahoma, 8pt)")> _
    <DesignerSerializationVisibility(DesignerSerializationVisibility.Content)> _
    Public Property AlternatingItemsCellStyle() As ListBoxCellStyle
            Return _AlternatingItemsCellStyle
        End Get
        Set(ByVal Value As ListBoxCellStyle)
            _AlternatingItemsCellStyle = Value
            AddHandler _AlternatingItemsCellStyle.AlternatingCellStyleChanged, AddressOf AlternatingCellStyleChanged
        End Set
    End Property
    Private Sub AlternatingCellStyleChanged(ByVal sender As Object, ByVal e As EventArgs)
    End Sub
    Private Sub ColoredListBox_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles Me.DrawItem
        Dim List As ListBox = CType(sender, ListBox)
        Dim Item As FormattedListItem = Nothing
        If TypeOf List.Items(e.Index) Is FormattedListItem Then
            Item = CType(List.Items(e.Index), FormattedListItem)
        End If
        Dim Font As Font = Nothing
        Dim ForeColor As Color = Color.Empty
        Dim BackColor As Color = Color.Empty
        Dim SelectionForeColor As Color = Color.Empty
        Dim SelectionBackColor As Color = Color.Empty
        If Item IsNot Nothing Then
            Font = Item.ListBoxItemsStyle.Font
            ForeColor = Item.ListBoxItemsStyle.ForeColor
            BackColor = Item.ListBoxItemsStyle.BackColor
            SelectionForeColor = Item.ListBoxItemsStyle.SelectionForeColor
            SelectionBackColor = Item.ListBoxItemsStyle.SelectionBackColor
            Font = List.Font
            ForeColor = List.ForeColor
            BackColor = List.BackColor
            SelectionForeColor = System.Drawing.SystemColors.HighlightText
            SelectionBackColor = System.Drawing.SystemColors.Highlight
        End If
        Dim ForeBrush As Brush
        Dim BackBrush As Brush
        If (e.State And DrawItemState.Selected) = DrawItemState.Selected Then
            ForeBrush = New SolidBrush(SelectionForeColor)
            BackBrush = New SolidBrush(SelectionBackColor)
            ForeBrush = New SolidBrush(ForeColor)
            BackBrush = New SolidBrush(BackColor)
        End If
        e.Graphics.FillRectangle(BackBrush, e.Bounds)
        Dim Text As String = List.Items(e.Index).ToString
        e.Graphics.DrawString(Text, Font, ForeBrush, e.Bounds.X, e.Bounds.Y)
    End Sub
    Private Sub ColoredListBox_MeasureItem(ByVal sender As Object, ByVal e As System.Windows.Forms.MeasureItemEventArgs) Handles Me.MeasureItem
        Dim List As ListBox = CType(sender, ListBox)
        If (IsPrimeNumber(e.Index)) Then
            Dim MyItem As New FormattedListItem(List.Items(e.Index), Me.AlternatingItemsCellStyle)
            If MyItem.ListBoxItemsStyle.Font IsNot Nothing Then
                List.Items.Insert(e.Index, MyItem)
                e.ItemHeight = MyItem.ListBoxItemsStyle.Font.Height
            End If
        End If
    End Sub
    Private Function IsPrimeNumber(ByVal [Number] As Integer) As Boolean
        Dim TheDouble As Double
        TheDouble = Double.Parse(([Number] / 2))
        If TheDouble.ToString.Contains(".") Then
            Return True
        End If
        Return False
    End Function
End Class

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1 Solution
Éric MoreauSenior .Net ConsultantCommented:

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