Android Realm中的一对多关系。 处理线程

Question

I have a one to many relationship relationship by having one song be assigned to a band, and a band has many songs. So in the end I am assigning song.setBand( band ). This all makes sense since the band is picked from a listView. The problem was when working with executeTransationAsync by trying to add the new song with the band. It worked if there was no band picked, but otherwise I was running with thread issues. I had to pick the band again while working withing the current thread. Is there a better solution to do this?

public void add( Song song ){

    int bandId = song.getBand().getId();

    realm.executeTransactionAsync(thisRealm->{

                Number nextID = thisRealm.where(Song.class).max("id");

                if( nextID != null ){
                    song.setId( nextID.intValue() + 1 );
                }else{
                    song.setId( 0 );
                }

                Band band = thisRealm.where(Band.class).equalTo( "id", bandId ).findFirst();

                if( band != null ){
                    song.setBand( band );
                }else{
                    song.setBand( null );
                }

                thisRealm.copyToRealm( song );
            },
            ()->{
                publishSubject.onNext( song );
            },
            error->{
                publishSubject.onError( error );
            });
}

Answer 1

As far as today Aug 29, 2016 this is the right way to save an object having a one to many relationship using an asynchronous transaction. Thanks for your help for those who left comments.