public ObservableCollection<SpreadsheetMenuCustomization> MenuCustomizations { get; set; }

Public Property MenuCustomizations As ObservableCollection(Of SpreadsheetMenuCustomization)

<dx:ThemedWindow x:Class="WpfSpreadsheetMenuCustomization.MainWindow" mc:Ignorable="d" 
                 Title="Spreadsheet" Height="450" Width="800"
    xmlns:dx="http://schemas.devexpress.com/winfx/2008/xaml/core"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:WpfSpreadsheetMenuCustomization"
    xmlns:dxsps="http://schemas.devexpress.com/winfx/2008/xaml/spreadsheet" 
    xmlns:dxb="http://schemas.devexpress.com/winfx/2008/xaml/bars">
    <Grid>
        <dxsps:SpreadsheetControl x:Name="spreadsheetControl">
            <dxsps:SpreadsheetControl.MenuCustomizations>
                <dxsps:SpreadsheetMenuCustomization MenuType="Cell">
                    <!--Add a separator after the first three menu items.-->
                    <dxb:InsertAction Index="3">
                        <dxb:BarItemSeparator />
                    </dxb:InsertAction>
                    <!--Insert a custom menu item under the separator
                    to highlight selected cells.-->
                    <dxb:InsertAction Index="4">
                        <dxb:BarButtonItem Content="Highlight Cells" 
                                           ItemClick="HighlightCells_ItemClick" />
                    </dxb:InsertAction>
                    <!--Append a new item to the end of the context menu
                    and bind this item to the spreadsheet command.-->
                    <dxb:BarButtonItem Command="{Binding RelativeSource={RelativeSource Self}, Mode=OneWay, 
                        Path=(dxsps:SpreadsheetControl.Spreadsheet).CommandProvider.MergeAndCenterCells}" 
                        Content="Merge Cells" />
                    <!--Change the Copy item's content.-->
                    <dxb:UpdateAction ElementName="{x:Static dxsps:DefaultBarItemNames.PopupMenuItem_Copy}" 
                                      PropertyName="Content" 
                                      Value="Copy Cells" />
                    <!--Remove the Insert Comment item from the menu.-->
                    <dxb:RemoveAction ElementName="{x:Static dxsps:DefaultBarItemNames.PopupMenuItem_InsertComment}" />
                    <!--Remove the Hyperlink item from the menu.-->
                    <dxb:RemoveAction ElementName="{x:Static dxsps:DefaultBarItemNames.PopupMenuItem_InsertHyperlink}" />
                </dxsps:SpreadsheetMenuCustomization>
            </dxsps:SpreadsheetControl.MenuCustomizations>
        </dxsps:SpreadsheetControl>
    </Grid>
</dx:ThemedWindow>

private void HighlightCells_ItemClick(object sender, DevExpress.Xpf.Bars.ItemClickEventArgs e)
{
    // Fill selected cells with the yellow color. 
    spreadsheetControl.Selection.FillColor = System.Drawing.Color.Yellow;
}

Private Sub HighlightCells_ItemClick(ByVal sender As Object, ByVal e As DevExpress.Xpf.Bars.ItemClickEventArgs)
    ' Fill selected cells with the yellow color. 
    spreadsheetControl.Selection.FillColor = System.Drawing.Color.Yellow
End Sub

<dxsps:SpreadsheetControl x:Name="spreadsheetControl">
    <dxsps:SpreadsheetControl.MenuCustomizations>
        <dxsps:SpreadsheetMenuCustomization MenuType="Cell">