extends StyleSelector to create your own style selector : StyleSelector « Windows Presentation Foundation « VB.Net Tutorial

1. VB.Net Tutorial
2. Windows Presentation Foundation
3. StyleSelector

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:WpfApplication1;assembly="
    Title="WPF" Height="248" Width="128">
    <Window.Resources>
        <local:Countries x:Key="countries"/>
        <Style x:Key="AlternateStyle">
            <Setter Property="ListBoxItem.Background" Value="LightGray"/>
        </Style>
    </Window.Resources>
    <Grid>
        <ListBox DisplayMemberPath="Name" ItemsSource="{Binding Source={StaticResource countries}}" >
            <ListBox.ItemContainerStyleSelector>
                <local:AlternatingRowStyleSelector AlternateStyle="{StaticResource AlternateStyle}" />
            </ListBox.ItemContainerStyleSelector>
        </ListBox>
    </Grid>
</Window>
//File:Window.xaml.vb
Imports System.Windows
Imports System.Windows.Controls
Imports System.Collections.ObjectModel
Namespace WpfApplication1
  Public Class AlternatingRowStyleSelector
    Inherits StyleSelector
    Public Property DefaultStyle() As Style
      Get
        Return m_DefaultStyle
      End Get
      Set
        m_DefaultStyle = Value
      End Set
    End Property
    Private m_DefaultStyle As Style

    Public Property AlternateStyle() As Style
      Get
        Return m_AlternateStyle
      End Get
      Set
        m_AlternateStyle = Value
      End Set
    End Property
    Private m_AlternateStyle As Style

    Private isAlternate As Boolean = False

    Public Overrides Function SelectStyle(item As Object, container As DependencyObject) As Style
      Dim style As Style = If(isAlternate, AlternateStyle, DefaultStyle)

      isAlternate = Not isAlternate

      Return style
    End Function
  End Class

  Public Class Country
    Private m_name As String
    Private m_continent As Continent

    Public Sub New(name As String, continent As Continent)
      Me.m_name = name
      Me.m_continent = continent
    End Sub

    Public Property Name() As String
      Get
        Return m_name
      End Get
      Set
        m_name = value
      End Set
    End Property

    Public Property Continent() As Continent
      Get
        Return m_continent
      End Get
      Set
        m_continent = value
      End Set
    End Property
  End Class
  Public Enum Continent
    Europe
    NorthAmerica
  End Enum
  Public Class Countries
    Inherits Collection(Of Country)
    Public Sub New()
      Me.Add(New Country("Great Britan", Continent.Europe))
      Me.Add(New Country("USA", Continent.NorthAmerica))
      Me.Add(New Country("Canada", Continent.NorthAmerica))
    End Sub
  End Class
End Namespace

16.127.StyleSelector
	16.127.1.	extends StyleSelector to create your own style selector