Radgridview row count in WPF

In this application I have radgridview when I click row expand the data will be loaded. When the user click on data row the user will drag the row data and drop in another row. The current row count data is updated instantly but the updated row count is not updating instantly. The user have given the code on radgridview selectionchanged event. Is there any way to get the radgridview updated instantly?

The above is radgridview in WPF. For eg when I click the row 29 value and drop in row 20 value. The row 29 will be decreased as 28 and row 20 is not updated as 21. This is the problem I am facing. As the code is placed as row selection changed event so when I expand the row, the row is updating. But the user needs to updated at same time instantly.

 

xaml.cs
        /// 

        /// Increase / Decrease the count during change  in grid.
        /// 
        private void Grid1_SelectionChanged(object sender, SelectionChangeEventArgs e)
        {
            var gridView = sender as RadGridView;

            var sampleViewModel = gridView.DataContext as SampleInformationBase;
            var masterViewModel = DataContext as SampleMasterViewModel;

            if (masterViewModel != null && sampleViewModel != null)
                gridView.ParentRow.Cells[3].Content = sampleViewModel.Count;
            
        }

The same functionality should happen but instantly both the row to be updated. But gridview selectionchanged means it will be updated during row selection. But I want to be updated when drag & drop itself.

 

StudentMasterViewModelBase

/// 

/// Handles a  that was dragged and dropped onto a 
/// 
/// 
protected virtual void DropStudent(object pParameter)
{
    
    if (pParameter is DragDropParameter)
    {
        var ddParameter = (pParameter as DragDropParameter);
        var recipientRoute = ddParameter.DropRecipient as RouteInformationBase;
        //int receipeRoutecount = recipientRoute.CustomerCount +1;
       
        if (recipientRoute != null)
        {
            RecipientRoute = recipientRoute.Route;

            var draggedItem = ddParameter.DraggedItem as StudentBase;

            draggedItem.Route = RecipientRoute;

            if (!recipientRoute.RouteStudents.Contains(draggedItem))
                recipientRoute.RouteStudents.Add(draggedItem);
         
        }
    }
    AutoNotifyPropertyChanged();
    
}


///

/// Handles when a  is added or removed from 
/// 
/// 
/// 
private void OnRouteStudentsChanged(object sender, NotifyCollectionChangedEventArgs e)
{
    
    if (e.Action == NotifyCollectionChangedAction.Add && e.NewItems != null)
    {
        foreach (StudentBase RouteStudent in e.NewItems)
        {
            // Subscribe to data object's EditEnded event
            RouteStudent.EditEnded += OnRouteStudentEdited;

            RouteStudent.BeginEdit();

            RouteStudent.EndEdit();
        }
    }

    if (e.Action == NotifyCollectionChangedAction.Remove && e.OldItems != null)
    {
        foreach (StudentBase RouteStudent in e.OldItems)
        {
            // Unsubscribe from the data object's EditEnded event
            RouteStudent.EditEnded -= OnRouteStudentEdited;
        }
    }
    AutoNotifyPropertyChanged();            
    
}


/// 

/// Handles when a  has been edited
/// 
/// 
private void OnRouteStudentEdited(object sender)
{
    if (sender is StudentBase StudentBase)
    {
        if (!string.IsNullOrWhiteSpace(StudentBase.Custno) && !string.IsNullOrWhiteSpace(RecipientRoute))
        {
            UpdateRouteChanges(StudentBase.Custno, RecipientRoute);
            OnRouteStudentSaved(sender as StudentBase);
        }
    }
    AutoNotifyPropertyChanged();
}


 /// 

 /// Ensures the recently-changed  exists in only one 
 /// 
 /// Recently-changed 
 private void OnRouteStudentSaved(object sender)
 {
     var RouteStudent = sender as StudentBase;

     if (RouteStudent != null && RouteData.Any())
     {
         var routeInformationCopy = new ObservableCollection(RouteData);

         foreach (RouteInformationBase route in routeInformationCopy)
         {
             if (route.Route != RouteStudent.Route)
             {
                 var match = route.RouteStudents.Where(x => x.Custno == RouteStudent.Custno).FirstOrDefault();

                 if (match != null)
                 {
                     var routeData = RouteData.Where(x => x.Route == route.Route).FirstOrDefault();
                     routeData.RouteStudents.Remove(match);
                 }
             }
         }
     }
     AutoNotifyPropertyChanged();
 }