private void SetSelectedItemsOnDropDown()
{
if (SelectedItems != null)
{
SelectedItems.Clear();
}
SelectedItems = (IList)Activator.CreateInstance(SelectedItems.GetType());
if (this.ItemsSource.Count > 0)
{
int index = 0;
foreach (var item in _itemList)
{
if (item.IsSelected)
{
SelectedItems.Add(ItemsSource[index]);
}
index++;
}
}
}