internal void AttachNode(Node node, ControlNode parentNode)
{
node.NodeSelectionChanged += NodeSelectionChanged;
node.NodeDirtyChanged += NodeDirtyChanged;
if (parentNode != null)
{
parentNode.AddChild(node);
}
else if (_rootNode == null)
{
_rootNode = node;
Dirty = true;
}
else
{
throw new InvalidOperationException("Can't attach orphaned node.");
}
}