private VirtualTreeItemInfo GetItemInfo(ref ITEMPOSITION pos, int column, bool setFlags, bool ignoreMultiColumn, bool lastSubItem)
{
var info = new VirtualTreeItemInfo(pos.ParentNode.Branch, pos.Index, column, pos.Level);
var blankItem = ignoreMultiColumn ? false : pos.IsBlank(column);
info.Blank = blankItem;
if (setFlags)
{
if (!ignoreMultiColumn && MultiColumnSupport)
{
TREENODE tnChild;
if (blankItem)
{
if (column >= pos.ParentNode.GetColumnCount(pos.Index))
{
// If the item is after all supported columns then
// just let it draw blank by leaving all flags clear.
info.ClearLevel();
}
else
{
Debug.Assert(pos.SubItemOffset > 0);
tnChild = pos.ParentNode.GetChildNode(pos.Index);
Debug.Assert(tnChild != null); // Can't get a subitem offset without a node
if (column == 0)
{
// A blank item in the first column
info.TrailingItem = pos.SubItemOffset == tnChild.ImmedSubItemGain;
info.LastBranchItem = (pos.Index + 1) == pos.ParentNode.ImmedCount;
info.FirstBranchItem = pos.Index == 0;
info.Expanded = tnChild.Expanded && (tnChild.ImmedCount > 0);
// Required information to draw lines down to expanded item
}
else
{
// A blank item in subitem column
info.ClearLevel();
info.TrailingItem = pos.SubItemOffset == tnChild.ImmedSubItemGain;
}
}
} // if (blankItem)
else if (!pos.ParentNode.MultiColumn)
{
info.Expanded = pos.IsExpanded(column);
info.Expandable = info.Expanded || pos.IsExpandable(column);
info.FirstBranchItem = pos.Index == 0;
info.LastBranchItem = pos.ParentNode.Branch.VisibleItemCount == (pos.Index + 1);
if (pos.ParentNode.InSubItemColumn)
{
info.LeadingItem = info.FirstBranchItem && pos.ParentNode.ComplexSubItem;
info.TrailingItem = lastSubItem;
info.SimpleCell = info.Level == 0 && pos.ParentNode.NoChildExpansion;
}
else
{
info.TrailingItem = info.LeadingItem = true;
}
}
else if (column == 0)
{
info.LeadingItem = true;
info.FirstBranchItem = pos.Index == 0;
info.LastBranchItem = (pos.Index + 1) == pos.ParentNode.ImmedCount;
tnChild = pos.ParentNode.GetChildNode(pos.Index);
if (tnChild == null)
{
info.TrailingItem = true;
info.Expandable = pos.IsExpandable(0); //column == 0
}
else
{
info.TrailingItem = tnChild.ImmedSubItemGain == 0;
info.Expanded = pos.IsExpanded(0); // column == 0
info.Expandable = info.Expanded || pos.IsExpandable(0);
}
info.SimpleCell = info.Level == 0 && pos.ParentNode.NoChildExpansion;
} // else if (column == 0)
else
{
info.LeadingItem = info.FirstBranchItem = true;
info.LastBranchItem = true;
tnChild = pos.ParentNode.GetChildNode(pos.Index);
if (tnChild != null)
{
info.TrailingItem = tnChild.ImmedSubItemGain == 0;
}
else
{
info.TrailingItem = true;
}
info.Expanded = pos.IsExpanded(column);
info.Expandable = info.Expanded || pos.IsExpandable(column);
info.SimpleCell = info.Level == 0 && !info.Expandable;
} // else
} // if (MultiColumnSupport)
else
{
Debug.Assert(column == 0);
if (!blankItem)
{
info.Expanded = pos.IsExpanded(column);
info.Expandable = info.Expanded ? true : pos.IsExpandable(column);
}
info.FirstBranchItem = pos.Index == 0;
info.LastBranchItem = pos.ParentNode.Branch.VisibleItemCount == (pos.Index + 1);
info.LeadingItem = info.TrailingItem = true;
} // else
}
return info;
}