private void UpdateRepeatedSoundsTreeNodes(IList <string> namesOfRepeatedSounds)
 {
     RepeatedSoundsTreeNodes.Clear();
     foreach (string name in namesOfRepeatedSounds)
     {
         TreeNode node = new TreeNode(name);
         RepeatedSoundsTreeNodes.Add(node);
     }
 }
        private void mainTreeView_BeforeLabelEdit(object sender, NodeLabelEditEventArgs e)
        {
            TreeNode nodeToEdit = e.Node;

            if (!RepeatedSoundsTreeNodes.Contains(nodeToEdit))
            {
                e.CancelEdit = true;
            }
            if (contextMenuForSoundTreeNodes.Visible == true)
            {
                e.CancelEdit = false;
            }
        }