<ListBox x:Name="DemoList" ScrollViewer.HorizontalScrollBarVisibility="Disabled">
            <ListBox.ItemsPanel>
                <ItemsPanelTemplate>
                    <WrapPanel />
                </ItemsPanelTemplate>
            </ListBox.ItemsPanel>
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <!--<RepeatButton Content="{Binding}" Width="55" Click="RepeatButton_Click" />-->
                    <TextBlock Text="{Binding}" TextAlignment="Right" Width="55" />
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

    Private Sub MainWindow_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Loaded
        DemoList.ItemsSource = Enumerable.Range(1, 10000)
    End Sub

    Private Sub DemoList_SelectionChanged(ByVal sender As Object, ByVal e As System.Windows.Controls.SelectionChangedEventArgs) Handles DemoList.SelectionChanged
        Console.WriteLine(DemoList.SelectedValue)
    End Sub
    'Private Sub RepeatButton_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs)
    '    Console.WriteLine(sender.content)
    'End Sub