private void buttonAdd_Click(object sender, RoutedEventArgs e)
        {
            System.Windows.Forms.FolderBrowserDialog folderBrowserDialog = new System.Windows.Forms.FolderBrowserDialog();
            folderBrowserDialog.Description = StringTable.ChooseMusicLibraryFolder;

            if (folderBrowserDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                // Prüfen, ob der ausgewählte Pfad bereits überwacht wird
                MusicLibraryFolder exists = allMusicLibraryFolders.SingleOrDefault(x => string.Compare(x.Path, folderBrowserDialog.SelectedPath, true) == 0);

                if (exists == null)
                {
                    AddFolder(folderBrowserDialog.SelectedPath);
                }
            }
            UpdateWindowState();
        }
        private void AddFolder(string folder)
        {
            MusicLibraryFolder newFolder = new MusicLibraryFolder();

            string title = System.IO.Path.GetFileName(folder);

            if (ShellLibrary.IsPlatformSupported)
            {
                try
                {
                    // Schmeißt ne Exception, wenn es kein Known Folder ist
                    IKnownFolder kf = KnownFolderHelper.FromPath(folder);
                    title = kf.LocalizedName;
                }
                catch
                { }
            }

            newFolder.Title = title;
            newFolder.Path  = folder;
            allMusicLibraryFolders.Add(newFolder);
        }