public class MainViewModel : ViewModelBase
{
    public MainViewModel(IEmployeeService employeeService)
    {
        IQueryable query = _employeeService.GetEmployees();
        this.Employees = new Telerik.Windows.Data.VirtualQueryableCollectionView(query) { LoadSize = 20 };
    }

    public Telerik.Windows.Data.VirtualQueryableCollectionView Employees { get; }
}