實現方式，通過自定義RowControl 的樣式實現。

參考：https://supportcenter.devexpress.com/ticket/list?searchString=RowCellMenuCustomizations%20show%20on%20left%20click&sorting=Relevance

<Window
    x:Class="Q433098.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 

    xmlns:dxe="http://schemas.devexpress.com/winfx/2008/xaml/editors"
    xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid"
    xmlns:dxgt="http://schemas.devexpress.com/winfx/2008/xaml/grid/themekeys"
    Width="525"
    Height="350"
    Title="MainWindow">

    <Window.Resources>
        <SolidColorBrush 
 
x:Key="UnfocusedRowBrush" Color="#FFDDDDDD" />
        <ControlTemplate x:Key="{dxgt:GridRowThemeKey ResourceKey=RowTemplate, ThemeName=Office2016White}" TargetType="dxg:RowControl">
            <Grid>
                <Border x:Name="Background" Background="{TemplateBinding Background}
 
" />
                <Border
                    x:Name="BottomLine"
                    VerticalAlignment="Bottom"
                    BorderBrush="{TemplateBinding BorderBrush}"
                    BorderThickness="0,0,0,1" />
                <Grid x:Name="PART_LayoutPanel" />
                <Border
                    x:Name="FocusedBorder"
                    Background="Transparent"
                    BorderBrush="Orange"
                    BorderThickness="2"
                    Visibility="{DXBinding '@p.SelectionState eq $dxg:SelectionState.Focused ? `Visible` : `Collapsed`'}" />
            </Grid>
            <ControlTemplate.Triggers>
                <Trigger Property="ShowHorizontalLine" Value="False">
                    <Setter TargetName="BottomLine" Property="Visibility" Value="Collapsed" />
                </Trigger>
                <Trigger Property="ShowBottomLine" Value="True">
                    <Setter TargetName="BottomLine" Property="Visibility" Value="Visible" />
                </Trigger>
                <Trigger Property="FadeSelection" Value="True">
                    <Setter Property="Background" Value="{StaticResource UnfocusedRowBrush}" />
                </Trigger>
                <Trigger Property="ShowRowBreak" Value="True">
                    <Setter TargetName="BottomLine" Property="BorderThickness" Value="{StaticResource {dxgt:GridRowThemeKey ResourceKey=RowBreakThickness}}" />
                    <Setter TargetName="BottomLine" Property="BorderBrush" Value="{StaticResource {dxgt:GridRowThemeKey ResourceKey=RowBreakBrush}}" />
                </Trigger>
                <Trigger Property="FixedRowPosition" Value="Bottom">
                    <Setter TargetName="BottomLine" Property="VerticalAlignment" Value="Top" />
                </Trigger>
                <Trigger Property="IsLastFixedRow" Value="True">
                    <Setter TargetName="BottomLine" Property="BorderThickness" Value="0,1,0,1" />
                    <Setter TargetName="BottomLine" Property="Background" Value="{DynamicResource {dxgt:GridRowThemeKey ResourceKey=RowSeparatorBrush}}" />
                </Trigger>
            </ControlTemplate.Triggers>
        </ControlTemplate>
    </Window.Resources>

    <Grid>
        <dxg:GridControl AutoGenerateColumns="AddNew" Name="gridControl1">
            <dxg:GridControl.View>
                <dxg:TableView />
            </dxg:GridControl.View>
        </dxg:GridControl>
    </Grid>

</Window>

完整Demo