RevitSdkSamples/SDK/Structural Analysis SDK/Examples/ExtensibleStorageUI/MainWindows.xaml

<Raf:WindowBase x:Class="ExtensibleStorageUI.MainWindows"
                xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                xmlns:Raf="clr-namespace:Autodesk.Revit.UI.ExtensibleStorage.Framework.WPF;assembly=ExtensibleStorageFramework.UI.WPF" 
                Title="ExtensibleStorageUI" Height="900" Width="900">
  <Grid>
    <Grid.RowDefinitions>
      <RowDefinition Height="28"></RowDefinition>
      <RowDefinition Height="*"></RowDefinition>
      <RowDefinition Height="37"></RowDefinition>
    </Grid.RowDefinitions>
    <Menu Grid.Row="0" IsMainMenu="True"></Menu>
    <DockPanel Grid.Row="1" Name="layout"></DockPanel>
        <DockPanel Grid.Row="2" Name="Command">
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width ="*"></ColumnDefinition>
                    <ColumnDefinition Width="175"></ColumnDefinition>
                </Grid.ColumnDefinitions>
                <Button Grid.Column="1" Content="OK" Height="23" Name="btnOk" Width="75" HorizontalAlignment="left" Margin="5,5" Click="btnOk_Click" />
                <Button Grid.Column="1" Content="Cancel" Height="23" Name="btnCancel" Width="75" HorizontalAlignment="Right" Margin="5,5" Click="btnCancel_Click" />
            </Grid>        
        </DockPanel>
    </Grid>
</Raf:WindowBase>