private void AssociatedObject_OnDragInitialize(object sender, DragInitializeEventArgs e)
{
e.Effects = DragDropEffects.All;
IList selectedItems = GetSelectedItemsAsList(AssociatedObject);
if (selectedItems.Count > 0)
{
if (GetItemContainerFromPoint(AssociatedObject, e.DragStartPosition) is FrameworkElement item)
{
Point mousePos = e.GetPosition(AssociatedObject);
Point itemPos = item.TranslatePoint(new Point(), AssociatedObject);
Point offset = new Point(mousePos.X - itemPos.X, mousePos.Y - itemPos.Y);
e.DragVisualSize = new Size(item.ActualWidth, item.ActualHeight);
e.DragVisualOffset = offset;
e.Data = DragDataManager.GenerateDataObject(selectedItems);
}
else
{
AssociatedObject.SelectedItems.Clear();
}
}
}
