private void symbolicExpressionTreeChart_DragDrop(object sender, DragEventArgs e)
{
Point coordinates = symbolicExpressionTreeChart.PointToClient(new Point(e.X, e.Y));
var node = symbolicExpressionTreeChart.FindVisualSymbolicExpressionTreeNodeAt(coordinates.X, coordinates.Y);
var root = symbolicExpressionTreeChart.Tree.Root;
var data = e.Data.GetData(HeuristicLab.Common.Constants.DragDropDataFormat);
var symbol = data as ISymbol;
var symbols = data as IEnumerable <ISymbol>;
if (node.Content == root)
{
if (symbol != null)
{
Grammar.AddAllowedChildSymbol(root.Symbol, symbol);
}
else if (symbols != null)
{
foreach (var s in symbols)
{
Grammar.AddAllowedChildSymbol(root.Symbol, s);
}
}
}
else
{
int argumentIndex = root.IndexOfSubtree(node.Content);
if (symbol != null)
{
Grammar.AddAllowedChildSymbol(root.Symbol, symbol, argumentIndex);
}
else if (symbols != null)
{
foreach (var s in symbols)
{
Grammar.AddAllowedChildSymbol(root.Symbol, s, argumentIndex);
}
}
}
BuildAllowedChildSymbolsTree();
}
