I have a vertical scroll bar on my XamGrid.

According to XamGrid's height it can show only six records.

It has one Template Column with RationButton.

The problem is when the data is more than six records lets say 10

at the time of loading if the radio button got selected on the first row as per the database value
and If I scoll down and select the radio button at the bottom and scroll up gain the radio button on the first row gets uncheched that is expected behaviour of Radion button. no issues at this point.

Then If I select the radion button on the first row and scroll down to the last row  the ratio button on the last row is also shows as checked.

Other thing is if I scroll up again back to the first row the first row is unchecked, I am not sure why it is unchecked

If I repeat this any number of times the first row is never getting selected.

Can some one help me on this?

I am using VS2010, Silverlight 4 and Infragistics's Netadvantage for Silverlithg Line of business V10.3

Here is the Xaml and code behind to bind the gird.

Xaml
----
<ig:XamGrid x:Name="xamGridEvents" ScrollViewer.VerticalScrollBarVisibility="Auto" AutoGenerateColumns="False" RowHeight="23"
                     CellClicked="xamGridEvents_CellClicked">

            <ig:XamGrid.SortingSettings>
                <ig:SortingSettings AllowSorting="False" ></ig:SortingSettings>
            </ig:XamGrid.SortingSettings>

            <ig:XamGrid.Columns>
                <ig:TextColumn HeaderText="Event" Key="EventType" IsReadOnly="True" HeaderTextHorizontalAlignment="Center" HorizontalContentAlignment="Center"  Width="80" />
                <ig:TemplateColumn HeaderText="Yes/No" Key="YesNoFlag" HorizontalContentAlignment="Center" Width="*"  >
                    <ig:TemplateColumn.ItemTemplate >
                        <DataTemplate >
                            <RadioButton HorizontalAlignment="Left" VerticalAlignment="Center" IsChecked="{Binding Path=YesNoFlag, Mode=TwoWay}"  GroupName="GroupradioButtonInEvent" Name="radioButtonInEvent"  />
                        </DataTemplate>
                    </ig:TemplateColumn.ItemTemplate>
                </ig:TemplateColumn>
            </ig:XamGrid.Columns>
        </ig:XamGrid>

Code behind
xamGridEvents.ItemsSource = e.Result.EventList;