public void AddDownload(MergedSong song)
{
SongItemDownloader downloader = new SongItemDownloader(musicSources, target, song);
downloader.DownloadFinish += Downloader_DownloadFinish;
songs.Add(downloader);
downloader.Download();
}
private void Downloader_DownloadFinish(object sender, SongItemDownloader e)
{
songs.Remove(e);
}