Yes. I did handle that event. But as I told you, after entering that event, it goes to the raisepropertychanged event for the phone number and allots the value. I have posted the code in the above post. 

Hello Gayathri,

Is it possible for you to send us an isolated sample project, where this is reproduced, so we could be able to investigate it further for you?

Looking forward for your reply.

Hi Stephan, Sorry I could not recreate it as it is passing through two viewmodels and one webservice. I will have to spend more time to recreate it than solve. I could able to get the phoneNumber property value inside XamGrid CellExitingEditMode

 private void XamGrid_CellExitingEditMode(object sender, Infragistics.Controls.Grids.ExitEditingCellEventArgs e)
        {
            CompanyPhoneNumbers newPhoneNumber = (CompanyPhoneNumbers)e.Cell.Row.Data;
            if (newPhoneNumber.PhoneNumber == "--")
            {
               // How to access maskeditor here to give the error message
            }
}

Thanks in advance.

Hello Gayathri,

You can get the Editor by using the ExitEditingCellEventArgs' Editor Property. Please let me know if you have further questions on this matter.

Looking forward for your reply.

I am getting the property inside the ExitEditingCellEventArgs of Xamgrid. Is there a way to access the xamMaskedEditor inside XamGrid's ExitEditingCellEventArgs, as the maskedEditor is a control inside the grid. If so, I can pass the error message to xamMaskedEditor from this event.

Thank you.

Thank you for the reply. Below is my usercontrol page structure.

I get nullreference again.

<UserControl x:Class="Debi.Sl.Rock.Views.Company.PhoneNumbersView"
    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:Controls="clr-namespace:Debi.Sl.Rock.Controls"             
    xmlns:design="clr-namespace:Debi.Sl.Rock.DesignerViewModels.Company"             
    xmlns:sdk="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data"             
    xmlns:ig="http://schemas.infragistics.com/xaml"
    xmlns:Converters="clr-namespace:Debi.Sl.Rock.Converters"
    xmlns:Interactivity="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
    xmlns:Behaviors="clr-namespace:Debi.Sl.Rock.Behaviors"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">

    <Controls:CollapsableContent HeaderText="Phone Numbers"
                                 IsExpanded="{Binding IsExpanded, Mode=TwoWay}"
                                 Style="{StaticResource CompanyCollapsableContentStyle}"
                                 d:DataContext="{d:DesignInstance design:PhoneNumbersDesignViewModel, IsDesignTimeCreatable=True}">
        <Controls:CollapsableContent.Resources>
            <Controls:DataContextBinder x:Key="BindingContent" Content="{Binding}" />
            <Converters:ComboEditorItemLookupConverter x:Key="LookupConverter"
                                                       LookupList="{Binding Source={StaticResource BindingContent}, Path=Content.PhoneTypeSearcher}" />
            <Converters:PhoneNumberConverter x:Key="PhoneConverter"/>
        </Controls:CollapsableContent.Resources>
        <Interactivity:Interaction.Behaviors>
            <Behaviors:ValidationBehavior HasBindingErrors="{Binding HasBindingErrors, Mode=TwoWay}" />
        </Interactivity:Interaction.Behaviors>
        <ig:XamGrid AutoGenerateColumns="False"
                    Height="200"
                    ItemsSource="{Binding PhoneNumbers}"
                    DeleteKeyAction="DeleteSelectedRows"
                    RowSelectorClicked="XamGrid_RowSelectorClicked"
                    CellExitingEditMode="XamGrid_CellExitingEditMode"                    
                    RowHover="Row"
                    VerticalAlignment="Top"
                    ColumnWidth="*">
            <ig:XamGrid.Columns>
                <ig:TemplateColumn Key="PhoneTypeId" HeaderText="Phone Type">
                    <ig:TemplateColumn.ItemTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding PhoneTypeId, Converter={StaticResource LookupConverter}}" />
                        </DataTemplate>
                    </ig:TemplateColumn.ItemTemplate>
                    <ig:TemplateColumn.EditorTemplate>
                        <DataTemplate>
                            <Controls:RockXamComboEditor
                                AutoComplete="True"
                                DisplayMemberPath="Name"
                                SelectedValuePath="Id"
                                SelectedValue="{Binding PhoneTypeId, Mode=TwoWay}"
                                ItemsSource="{Binding Source={StaticResource BindingContent}, Path=Content.PhoneTypes}">
                            </Controls:RockXamComboEditor>
                        </DataTemplate>
                    </ig:TemplateColumn.EditorTemplate>
                </ig:TemplateColumn>
                <ig:TemplateColumn Key="PhoneNumber" HeaderText="Phone Number" Width="*">
                    <ig:TemplateColumn.ItemTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding PhoneNumber, Converter={StaticResource PhoneConverter}}" />
                        </DataTemplate>
                    </ig:TemplateColumn.ItemTemplate>
                    <ig:TemplateColumn.EditorTemplate>
                        <DataTemplate>
                            <Grid>
                            <ig:XamMaskedEditor Mask="999-999-9999CCCCCCCC" x:Name="xamMask" Value="{Binding PhoneNumber, Mode=Twoway}" ValueChanged="XamMaskEditor_ValueChanged" AcceptsReturn="True">                               
                            </ig:XamMaskedEditor>
                            </Grid>
                        </DataTemplate>
                    </ig:TemplateColumn.EditorTemplate>
                </ig:TemplateColumn>                
            </ig:XamGrid.Columns>
            <ig:XamGrid.AddNewRowSettings>
                <ig:AddNewRowSettings AllowAddNewRow="Bottom"
                                      IsEnterKeyEditingEnabled="False"
                                      IsF2EditingEnabled="True"
                                      IsMouseActionEditingEnabled="SingleClick"
                                      IsOnCellActiveEditingEnabled="False"/>
            </ig:XamGrid.AddNewRowSettings>
            <ig:XamGrid.EditingSettings>
                <ig:EditingSettings
                    AllowEditing="Row"
                    IsMouseActionEditingEnabled="SingleClick" />
            </ig:XamGrid.EditingSettings>
            <ig:XamGrid.SelectionSettings>
                <ig:SelectionSettings RowSelection="Multiple" CellClickAction="SelectRow" />
            </ig:XamGrid.SelectionSettings>
            <ig:XamGrid.RowSelectorSettings>
                <ig:RowSelectorSettings EnableRowNumbering="False" Visibility="Visible" />
            </ig:XamGrid.RowSelectorSettings>            
        </ig:XamGrid>
    </Controls:CollapsableContent>
</UserControl>

Hi Krasimir, Thanks for the reply. I get a NullReferenceException on XamMaskedEditor. Following is my code.

private void XamGrid_CellExitingEditMode(object sender, Infragistics.Controls.Grids.ExitEditingCellEventArgs e)

{

CompanyPhoneNumbers newPhoneNumber = (CompanyPhoneNumbers)e.Cell.Row.Data;

if (newPhoneNumber.PhoneNumber == "--")

{

Grid grid = e.Editor as Grid;

//XamMaskedEditor input= e.Editor as XamMaskedEditor -- this is also throwing nullreference.

XamMaskedEditor input = grid.Children[0] as XamMaskedEditor;

input.ErrorMessage = "Please enter a valid phone Number";

input.Focus();

return;

}

}