Window1.xaml

<Window
    x:Class="DXContextMenu_Ex.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:dxb="http://schemas.devexpress.com/winfx/2008/xaml/bars"
    Height="300" Width="300"
    Title="Window1">
    <Grid>
        <DockPanel>
            <TextBox
                x:Name="textEdit1"
                Width="200"
                Height="30"
                Text="right-click this textbox">
                <dxb:BarManager.DXContextMenu>
                    <dxb:PopupMenu>
                        <dxb:PopupMenu.Items>
                            <dxb:BarButtonItem
                                Content="Copy"
                                Glyph="pack://application:,,,/Images/copy16x16.png"
                                ItemClick="itemCopy_ItemClick" />
                            <dxb:BarButtonItem
                                Content="Paste"
                                Glyph="pack://application:,,,/Images/paste16x16.png"
                                ItemClick="itemPaste_ItemClick" />
                            <dxb:BarButtonItem
                                Content="Undo"
                                Glyph="pack://application:,,,/Images/undo16x16.png"
                                ItemClick="itemUndo_ItemClick" />
                            <dxb:BarButtonItem
                                Content="Redo"
                                Glyph="pack://application:,,,/Images/redo16x16.png"
                                ItemClick="itemRedo_ItemClick" />
                        </dxb:PopupMenu.Items>
                    </dxb:PopupMenu>
                </dxb:BarManager.DXContextMenu>
            </TextBox>
        </DockPanel>
    </Grid>
</Window>