MusicPicker

private async void button_Click(object sender, RoutedEventArgs e)
        {
            StorageFolder picturesFolder = await KnownFolders.GetFolderForUserAsync(null /* current user */, KnownFolderId.MusicLibrary);

            IReadOnlyList<StorageFile> fileList = await picturesFolder.GetFilesAsync();
            IReadOnlyList<StorageFolder> folderList = await picturesFolder.GetFoldersAsync();

            var count = fileList.Count + folderList.Count;

            StringBuilder outputText = new StringBuilder(picturesFolder.Name + " (" + count + ")\n\n");

            foreach (StorageFolder folder in folderList)
            {
                Button submitButton = new Button();
                submitButton.Content = folder.DisplayName;
                submitButton.Click += SubmitButton_Click;
                OutputPanel.Children.Add(submitButton);
            }

            foreach (StorageFile file in fileList)
            {
                outputText.AppendLine(file.Name);
            }

            OutputTextBlock.Text = outputText.ToString();

        }