/// <summary>
/// Process drop operations in self relational view.
/// </summary>
/// <param name="rowColumnIndex">dropped row column index.</param>
/// <param name="dropPosition">drop position.</param>
/// <param name="nodes">the dragging nodes which needs to be dropped.</param>
/// <param name="sourceTreeGrid">the grid from which drag operation in initiated.</param>
protected virtual void ProcessDropOnSelfRelationalView(RowColumnIndex rowColumnIndex, DropPosition dropPosition, ObservableCollection <TreeNode> nodes, SfTreeGrid sourceTreeGrid)
{
var isSameGrid = (TreeGrid == sourceTreeGrid);
var treeNode = this.TreeGrid.GetNodeAtRowIndex(rowColumnIndex.RowIndex);
if (treeNode == null)
{
return;
}
var data = treeNode.Item;
object parentPropertyValue = null;
TreeGrid.View.Suspend();
TreeGrid.SelectionController.SuspendUpdates();
ProcessDragSourceOnDrop(sourceTreeGrid, nodes);
TreeNode parentNode = null;
if (dropPosition == DropPosition.DropBelow || dropPosition == DropPosition.DropAbove)
{
parentNode = treeNode.ParentNode;
}
else if (dropPosition == DropPosition.DropAsChild)
{
if (!treeNode.IsExpanded)
{
TreeGrid.ExpandNode(treeNode);
}
parentNode = treeNode;
}
var itemIndex = -1;
var nodeIndex = -1;
IList sourceCollection = TreeGridHelper.GetSourceListCollection(TreeGrid.View.SourceCollection);
if (dropPosition == DropPosition.DropAsChild)
{
itemIndex = sourceCollection.Count;
nodeIndex = parentNode.ChildNodes.Count;
}
else if (dropPosition == DropPosition.DropBelow || dropPosition == DropPosition.DropAbove)
{
itemIndex = sourceCollection.IndexOf(data);
if (parentNode != null)
{
nodeIndex = parentNode.ChildNodes.IndexOf(treeNode);
}
else
{
nodeIndex = this.TreeGrid.View.Nodes.RootNodes.IndexOf(treeNode);
}
if (dropPosition == DropPosition.DropBelow)
{
itemIndex += 1;
nodeIndex += 1;
}
}
var propertyAccessProvider = TreeGrid.View.GetPropertyAccessProvider();
if (parentNode != null)
{
parentPropertyValue = propertyAccessProvider.GetValue(parentNode.Item, TreeGrid.ParentPropertyName);
}
else
{
if (TreeGrid.ReadLocalValue(SfTreeGrid.SelfRelationRootValueProperty) != DependencyProperty.UnsetValue)
{
parentPropertyValue = TreeGrid.SelfRelationRootValue;
}
}
foreach (var node in nodes)
{
if (parentNode == null && TreeGrid.ReadLocalValue(SfTreeGrid.SelfRelationRootValueProperty) == DependencyProperty.UnsetValue)
{
if (isSameGrid)
{
parentPropertyValue = GetChildPropertyValue(node);
}
else
{
parentPropertyValue = GetChildPropertyValue(treeNode);
}
}
SetValue(node.Item, TreeGrid.ChildPropertyName, propertyAccessProvider, parentPropertyValue);
sourceCollection.Insert(itemIndex, node.Item);
if (isSameGrid)
{
this.TreeGrid.View.AddNode(parentNode, node, nodeIndex, needDataShaping: false);
}
else
{
(this.TreeGrid.View as TreeGridSelfRelationalView).CheckPrimaryKey();
this.TreeGrid.View.AddNode(parentNode, node.Item, nodeIndex, false);
}
}
UpdateParentNodeExpanderCell(parentNode);
this.TreeGrid.View.Resume();
TreeGrid.SelectionController.ResumeUpdates();
(TreeGrid.SelectionController as TreeGridRowSelectionController).RefreshSelection();
}
