Hi,
I have a validation like below in xamDataGrid:

<ig:Field Name="EmailAddress" Label="{tp:Localize FieldLabelEmail}">
    <ig:Field.Settings>
        <ig:FieldSettings EditorType="{x:Type Editors1:XamTextEditor}">
            <ig:FieldSettings.EditorStyle>
                <Style TargetType="{x:Type Editors1:ValueEditor}">
                    <Style.Setters>
                        <Setter Property="ValueConstraint">
                            <Setter.Value>
                                <Editors1:ValueConstraint MinLength="5" RegexPattern="^(([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25})+([;.](([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25})+)*$" />
                            </Setter.Value>
                        </Setter>
                        <Setter Property="InvalidValueBehavior" Value="RetainValue" />
                    </Style.Setters>
                    <Style.Triggers>
                        <Trigger Property="IsValueValid" Value="false">
                            <Trigger.Setters>
                                <Setter Property="BorderBrush" Value="Red" />
                            </Trigger.Setters>
                        </Trigger>
                    </Style.Triggers>
                </Style>
            </ig:FieldSettings.EditorStyle>
        </ig:FieldSettings>
    </ig:Field.Settings>
</ig:Field>

I'm trying to figure it out how to customize validation error message box (replace by my own implementation), for now, I could just turn off the