如何将realmobject添加到realmist?

我尝试将SongRealm添加到SongListRealm,如下所示:

public void insertSongToListWithKey(final int key, Song song){
    final SongRealm songRealm = mapper.toRealm(song);
    realm.beginTransaction();

    SongListRealm songListRealm = realm.where(SongListRealm.class).equalTo("key", key).findFirst();
    if(songListRealm!=null){
        songListRealm.getSongList().add(songRealm);
        realm.insertOrUpdate(songListRealm);
    }

    realm.commitTransaction();
}

之前:

歌曲列表名为“A”歌曲名为“1”,歌曲名为“2”

歌曲列表名为“B”歌曲名为“14”

后:

歌曲列表名为“A”歌曲名为“4”,歌曲名为“4”

歌曲列表名为“B”歌曲名为“4”,歌曲名为“4”

我做错什么了?祝你晚上愉快。提前谢谢你。

编辑

我正在添加更多代码:)

SongListMapper(类更改SongList上的SongListRealm)方法:

public SongList fromRealm(SongListRealm songListRealm){
    SongList songList = new SongList();
    ArrayList<Song> songArrayList = new ArrayList<>();
    RealmList<SongRealm> realmSongList = songListRealm.getSongList();
    for(SongRealm songRealm: realmSongList){
        songArrayList.add(songMapper.fromRealm(songRealm));
    }
    songList.setSongList(songArrayList);
    songList.setTitle(songListRealm.getName());
    songList.setKey(songListRealm.getKey());
    return songList;
}

SongMapper(在Song上更改SongRealm的类,反之亦然):

public Song fromRealm(SongRealm songRealm){
    Song song = new Song();
    song.setArtist(songRealm.getArtist());
    song.setId(songRealm.getId());
    song.setPath(songRealm.getPath());
    song.setTitle(songRealm.getTitle());
    return song;
}

getAllTheSongLists()方法:

public ArrayList<SongList> getAllTheSongLists() {
    ArrayList<SongList> songs = new ArrayList<>();
    SongListMapper mapper = new SongListMapper();
    RealmResults<SongListRealm> all = realm.where(SongListRealm.class).findAll().sort("key");
    for (SongListRealm songRealm : all) {
        if(songRealm.getKey()==idLastSongListValue)
            continue;
        songs.add(mapper.fromRealm(songRealm));
    }
    return songs;
}

我在idlastSongListValue变量中保存键为的上次使用的SongList,所以它不是用户创建的SongList,我不想为用户显示它。

[解决]

我必须用新的主键创建新的对象,并将song对象的变量设置为创建songrealm对象和从epicpandaforce复制方法。希望它能帮助你。

public void insertSongToListWithKey(final int key, final Song song){
    realm.executeTransaction(new Realm.Transaction() {
        @Override
        public void execute(Realm r) {
            SongRealm songRealmNew = createSongRealm(song);
            SongListRealm songListRealm = realm.where(SongListRealm.class).equalTo("key", key).findFirst();
            if (songListRealm != null) {
                SongRealm savedSongRealm = realm.copyToRealmOrUpdate(songRealmNew);
                RealmList<SongRealm> songs = songListRealm.getSongList();
                if(!songs.contains(savedSongRealm)) {
                    songs.add(savedSongRealm);
                }
            }
        }
    });
}

private SongRealm createSongRealm(Song song){
    SongRealm songRealmNew = realm.createObject(SongRealm.class, generateIdForSong());
    songRealmNew.setId(song.getId());
    songRealmNew.setTitle(song.getTitle());
    songRealmNew.setPath(song.getPath());
    songRealmNew.setArtist(song.getArtist());
    return songRealmNew;
}

 private int generateIdForSong() {
    if(realm.where(SongRealm.class).max("key")==null)
        return 0;
    return realm.where(SongRealm.class).max("key").intValue() + 1;
 }