public static FilterTreeNode AddRootNode(TreeView tree, Filter rootItem)
 {
     FilterTreeNode root = new FilterTreeNode();
     root.Item = rootItem;
     tree.Nodes.Add(root);
     return root;
 }
 public static void AddChildNodes(TreeNode parent, List<SpendFilter> filters)
 {
     foreach (var filter in filters)
     {
         FilterTreeNode node = new FilterTreeNode();
         node.Item = filter;
         parent.Nodes.Add(node);
     }
 }