<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        Title="MainWindow" Height="600" Width="800">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="50"/>
        </Grid.RowDefinitions>
        <telerik:RadGridView x:Name="radGridView" ItemsSource="{Binding}" 
                             EnableRowVirtualization="True"
                             ScrollMode="Deferred"
                             SelectionMode="Extended"/>
        <Button Grid.Row="1" Content="Clear Selection" Click="Button_Click" Height="40" />
    </Grid>
</Window>
