android - MediaStore.Audio.Artists 中没有 "number_of_albums column"

Question

我想从 MediaStore 中检索数据，尤其是每个艺术家的专辑数量，但 SQLite 抛出异常

no such column: number_of_albums (code 1): while compiling: SELECT artist_key, artist, number_of_albums FROM audio WHERE (is_music != 0)

谁能解释一下我做错了什么？

我的代码:

private List<Artist> getArtistList() {
    String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";

    String[] projection = {
            MediaStore.Audio.Artists.ARTIST_KEY,
            MediaStore.Audio.Artists.ARTIST,
            MediaStore.Audio.Artists.NUMBER_OF_ALBUMS
    };

    Cursor cursor = this.getActivity().getApplicationContext().getContentResolver().query(
            MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
            projection,
            selection,
            null,
            null);

    List<Artist> artists = new ArrayList<Artist>();
    Artist tmp = null;

    if (cursor.moveToFirst()) {
        do {    
            tmp = new Artist(cursor.getString(0),
                    cursor.getString(1),
                    Integer.parseInt(cursor.getString(2)));
            artists.add(tmp);
        } while (cursor.moveToNext());
    }

    return artists;
}

谢谢!

Answer 1

您正在为该列查询错误的内容 URI。使用 MediaStore.Audio.Artists.EXTERNAL_CONTENT_URI 而不是 MediaStore.Audio.Media.EXTERNAL_CONTENT_URI。