问RecyclerView插入arrayList计数动画

EN

 /* Retrive  data from database */
public List<AudioItem> getDataFromDB(){
    List<AudioItem> audioList = new ArrayList<>();
    String query = "select * from " + TABLE_NAME;

    SQLiteDatabase db = this.getWritableDatabase();
    Cursor cursor = db.rawQuery(query,null);

    if (cursor.moveToFirst()){
        do {
            AudioItem audio = new AudioItem();
            audio.setId(Integer.parseInt(cursor.getString(0)));
            audio.setName(cursor.getString(1));
            audio.setFilePath(cursor.getString(2));
            audio.setLength(Integer.parseInt(cursor.getString(3)));
            audio.setTime(Long.parseLong(cursor.getString(4)));
            audioList.add(audio);

        }while (cursor.moveToNext());
        cursor.close();
    }

    return audioList;
}

    db = new DatabaseHelper(this);
    dbList = new ArrayList<>();
    dbList = db.getDataFromDB();


    itemList = new ArrayList<>();
    for (int i=0; i<dbList.size(); i++) {
        if (dbList.get(i).getName().contains(titleName))
            itemList.add(dbList.get(i));
    }

    RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    mRecyclerView.setHasFixedSize(true);
    LinearLayoutManager llm = new LinearLayoutManager(this);
    llm.setOrientation(LinearLayoutManager.VERTICAL);

    //newest to oldest order (database stores from oldest to newest)
    llm.setReverseLayout(true);
    llm.setStackFromEnd(true);

    mRecyclerView.setLayoutManager(llm);
    mRecyclerView.setItemAnimator(new DefaultItemAnimator());

    adapter = new RecyclerAdapter(this, llm, itemList);
    mRecyclerView.setAdapter(adapter);

@Override
public int getItemCount() {
    return itemList.size();
}

@Override
public void onNewDatabaseEntryAdded() {
    //item added to top of the list
    Log.e("Count: ", Integer.toString(getItemCount()));
    notifyItemInserted(getItemCount() - 1);
    llm.scrollToPosition(getItemCount() - 1);
}