当列表视图项被选中时播放歌曲

我想让用户从列表视图中选择一首歌曲并播放它。我试过了:listview.SelectedValuePath我得到一个错误:Url是空白。我尝试了:listview.SelectedItem.ToString()我得到一个错误:无效的Url。Listview项文本是文件路径。所以不是这样的。我的完整代码:

FileOpenPicker picker = CreateFilePicker(audioExtensions);
IReadOnlyList<StorageFile> files = await picker.PickMultipleFilesAsync();
if (files != null && files.Count > 0)
{
    playlist = new Playlist();
    foreach (StorageFile file in files)
    {
        playlist.Files.Add(file);
        StorageFile savedFile =
            await playlist.SaveAsAsync(KnownFolders.MusicLibrary,
                                       "Sample",
                                       NameCollisionOption.ReplaceExisting,
                                       PlaylistFormat.WindowsMedia);
        this.OutputStatus.Text = savedFile.Name + " was created and saved with "
                                 + playlist.Files.Count + " files."
                                 + Environment.NewLine + "At folder: "
                                 + savedFile.Path;
        listview.Items.Add(file.Path.ToString());
    }
}
else
{
    this.OutputStatus.Text = "No files picked.";
}

My Listview changed:

   private void listview_SelectionChanged(object sender, SelectionChangedEventArgs e)
   {
                media.Source = new Uri(listview.SelectedValuePath);
   }