/// <summary>
        /// Default constructor
        /// </summary>
        public DirectoryStructureViewModel()
        {
            // Get the logical drives
            var children = DirectoryStructure.GetLogicalDrives();

            // Create the view models from the data
            this.Items = new ObservableCollection <DirectoryItemViewModel>(
                children.Select(drive => new DirectoryItemViewModel(drive.FullPath, DirectoryItemType.Drive)));
        }