private void Delete(DataFolderViewModel dataFolderViewModel)
        {
            var index = DataFolders.IndexOf(dataFolderViewModel);

            if (index < 0)
            {
                return;
            }
            DataFolders.RemoveAt(index);
        }
        private void MoveDown(DataFolderViewModel dataFolderViewModel)
        {
            var index = DataFolders.IndexOf(dataFolderViewModel);

            if (index < 0 || index >= DataFolders.Count - 1)
            {
                return;
            }
            DataFolders.RemoveAt(index);
            DataFolders.Insert(index + 1, dataFolderViewModel);
        }
        private void MoveUp(DataFolderViewModel dataFolderViewModel)
        {
            var index = DataFolders.IndexOf(dataFolderViewModel);

            if (index <= 0)
            {
                return;
            }
            DataFolders.RemoveAt(index);
            DataFolders.Insert(index - 1, dataFolderViewModel);
        }