private void _getListAllBook()
    {
        Debug.Log(" saving textAsset " + fileSave);
        string loadedText = File.ReadAllText(fileSave);

        ///Debug.Log("textAsset loaded=" + loadedText);
        listAllBooks = JsonUtility.FromJson <ListBookInfos>(loadedText);
    }
    public void saveBooksToLocal(System.Action callbackWhenDone)
    {
        GlobalVar.shareContext.loadingIndicator.SetActive(true);
        dbf.Child("public").Child("vn").Child("books").GetValueAsync().ContinueWith(task => {
            if (task.IsFaulted)
            {
                // Handle the error...
            }
            else if (task.IsCompleted)
            {
                DataSnapshot snapshot   = task.Result;
                List <BookInfo> lsbooks = new List <BookInfo>();
                foreach (var item in snapshot.Children)
                {
                    //  Debug.Log("b id="+item.Key+"/ v="+item.GetRawJsonValue());
                    BookInfo b = JsonUtility.FromJson <BookInfo>(item.GetRawJsonValue());
                    b.id       = item.Key;
                    if (b.dependencies != null)
                    {
                        Debug.Log("b id=" + item.Key + "/ v=" + b.dependencies[0]);
                    }
                    lsbooks.Add(b);
                }
                ListBookInfos bs = new ListBookInfos();
                bs.books         = lsbooks.ToArray();
                bs.db_version    = 1;
                string jsonBooks = JsonUtility.ToJson(bs, true);

                Debug.Log(jsonBooks);

                Debug.Log(" saving textAsset " + fileSave);
                File.WriteAllText(fileSave, jsonBooks);
                Debug.Log(" saved textAsset");

                string loadedText = File.ReadAllText(fileSave);
                Debug.Log("textAsset loaded=" + loadedText);
                callbackWhenDone();
                GlobalVar.shareContext.loadingIndicator.SetActive(false);
            }
        });
    }
 public void reSaveBooksToLocal(System.Action callbackWhenDone)
 {
     listAllBooks = null;
     saveBooksToLocal(callbackWhenDone);
 }