Hello Sreek,

I have investigated the custom FieldChooser functionality you are trying to achieve with explicit binding  and I recommend you to set the e.Cancel to true in the FieldChooserOpening event and put up your custom dialog instead of re-templating the FieldChooser. Having the custom dialog will allow you to control the look and the behavior of the element.  I have modified the attached sample application in order to show you how can create custom FieldChooser with the functionality you want.

Basically I have added EntryModel class which contains properties for field name, isvisible and category. In the Grid I have added our XamDialogWindow with XamDataGrid  that has similar fields and setting like in your application, so in the FieldChooserOpening I canceled the default FieldChooser window and open our XamDialogWindow. I created ObservableCollection<EntryModel>  FChooserEntry, in order to get the fields, their visibility and category. Then I set the XamDataGrid’s DataContext to be FChooserEntry collection and also handle the WindowStateChanged event of dialog window. This way we can check and uncheck the fields and then when we close the dialog we may  iterate through the Fields from main grid and set Visibility to be equal to the corresponding property from FChooserEntry collection, for example:

<ig:XamDialogWindow WindowState="Hidden" Name="dialog"  Width="350" Height="300" 
 IsModal="False" StartupPosition="Center" >
     <ig:XamDialogWindow.Content>
         <igDP:XamDataGrid Name="xdgInChooser" DataSource="{Binding}"  >
             <igDP:XamDataGrid.FieldSettings>
                 <igDP:FieldSettings AllowRecordFiltering="true"/>
             </igDP:XamDataGrid.FieldSettings>
             <igDP:XamDataGrid.FieldLayouts>
                 <igDP:FieldLayout>
                     <igDP:FieldLayout.Fields>
                         <igDP:CheckBoxField Name="IsVisible">
                             <igDP:CheckBoxField.Settings>
                                 <igDP:FieldSettings   CellMaxWidth="100" AllowEdit="true"  >
                                 </igDP:FieldSettings>
                             </igDP:CheckBoxField.Settings>
                         </igDP:CheckBoxField>
                         <igDP:Field  Name="Category">
                             <igDP:Field.Settings>
                                 <igDP:FieldSettings CollapseWhenEmpty="True" />
                             </igDP:Field.Settings>
                         </igDP:Field>
                     </igDP:FieldLayout.Fields>
                     <igDP:FieldLayout.SortedFields>
                         <igDP:FieldSortDescription FieldName="Category" Direction="Ascending" IsGroupBy="True"/>
                     </igDP:FieldLayout.SortedFields>
                 </igDP:FieldLayout>
             </igDP:XamDataGrid.FieldLayouts>
         </igDP:XamDataGrid>
     </ig:XamDialogWindow.Content>
 </ig:XamDialogWindow> 

private void xdg_FieldChooserOpening(object sender, Infragistics.Windows.DataPresenter.Events.FieldChooserOpeningEventArgs e)
{
    FChooserEntry = new ObservableCollection<EntryModel>();
    e.Cancel = true;

    foreach (var entry in xdg.FieldLayouts[0].Fields)
    {
        FChooserEntry.Add(new EntryModel()
        {
            FName = entry.Name.ToString(),
            IsVisible = (entry.Visibility == Visibility.Visible) ? true : false ,  
            Category = entry.Tag.ToString()
        });
    }
    xdgInChooser.DataContext = FChooserEntry;
    dialog.WindowState = Infragistics.Controls.Interactions.WindowState.Normal;
    dialog.WindowStateChanged += Dialog_WindowStateChanged;
} 

private void Dialog_WindowStateChanged(object sender, Infragistics.Controls.Interactions.WindowStateChangedEventArgs e)
{
    if (e.NewWindowState == Infragistics.Controls.Interactions.WindowState.Hidden)
    {
        int i = xdg.FieldLayouts[0].Fields.Count - 1;
        while (i >= 0)
        {
            switch (FChooserEntry[i].IsVisible)
            {
                case false:
                    xdg.FieldLayouts[0].Fields[i].Visibility = Visibility.Collapsed;
                    i--;
                    break;
                default:
                    xdg.FieldLayouts[0].Fields[i].Visibility = Visibility.Visible;
                    i--;
                    break;
            }

        }
    }
}

Thank you Zhivko.

Hello Sreek,

I was able to reproduce your behavior and I can say that this is the designed behavior caused by the Recycle mode of virtualization in XamDataGrid. 

The virtualization is  a feature which highly improve the performance in the application if you are loading a large number of records at a time. The idea behind virtualization is that only the visible rows are rendered in the grid, and these rendered records are used later as a container for the generated data. As users start to scroll the grid data in the pool of rows is updated and the records elements are reused.