public void GetItemGroup(int itemIndex, int occurrenceCount, out int groupIndex) {
groupIndex = -1;
var itemControlWide = this._VirtualListView.Items[itemIndex];
//if (this._VirtualListView.IsGroupsEnabled && itemControlWide.GroupIndex == -1)
//{
// foreach (var group in this._VirtualListView.Groups) {
// if (group.Items.Any(c => c.Equals(itemControlWide))) {
// groupIndex = group.Index;
// break;
// }
// }
//}
//else
//{
groupIndex = itemControlWide.GroupIndex;
//}
}
}