public class MsgChatActivity extends AppCompatActivity {

    Socket mSocket;

    MsgHistoryAPIService msgHistoryAPIService;
    RecyclerView recyclerView;
    ChatConversationAdapter chatAdapter;
    List<Datum> data = new ArrayList<>();


    String frId_TV, owner_type_TV, subject_TV;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_msg_chat);

        // initialize Socket
        ChatApplication app = (ChatApplication) getApplication();
        mSocket = app.getSocket();
        mSocket.on(Socket.EVENT_CONNECT, onConnect);
        mSocket.on(username, onNewMessage);
        mSocket.connect();


        msgHistoryAPIService = RestClient.getClient().create(MsgHistoryAPIService.class);

        recyclerView = (RecyclerView) findViewById(R.id.reyclerview_message_list);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));

        chatAdapter = new ChatConversationAdapter(getApplicationContext(),data);
        recyclerView.setAdapter(chatAdapter);

        frId_TV = "1";
        owner_type_TV = "1";
        subject_TV = "Message";

        chatHistoryData();

    }



    private void chatHistoryData() {
            final MsgHistoryRequest msgHistoryRequest = new MsgHistoryRequest(
            frId_TV,
            owner_type_TV,
            subject_TV
            );

            Call<MsgHistoryResponse> call = msgHistoryAPIService.chatHistory(token_key,
                    msgHistoryRequest);
            call.enqueue(new Callback<MsgHistoryResponse>() {
                @Override
                public void onResponse(Call<MsgHistoryResponse> call, Response<MsgHistoryResponse> response) {
                    Toast.makeText(MsgChatActivity.this, "" +response.body().getStatus() , Toast.LENGTH_LONG).show();

                    data.addAll(response.body().getData());
                    Toast.makeText(MsgChatActivity.this, "" + data.size(), Toast.LENGTH_LONG).show();
                    chatAdapter.notifyDataSetChanged();
                }

                @Override
                public void onFailure(Call<MsgHistoryResponse> call, Throwable t) {

                    Toast.makeText(MsgChatActivity.this, "please try again" , Toast.LENGTH_LONG).show();
                }
            });
    }


    private Emitter.Listener onConnect = new Emitter.Listener(){
        @Override
        public void call(Object... args) {

        }
    };


    public Emitter.Listener onNewMessage = new Emitter.Listener(){

        @Override
        public void call(final Object... args) {
            MsgChatActivity.this.runOnUiThread(new Runnable(){

                @Override
                public void run() {
                    //args[i] is the data received
                    JSONObject abc = (JSONObject) args[0];

                    Toast.makeText(MsgChatActivity.this, ""+ abc,
                            Toast.LENGTH_LONG).show();
                }
            });

        }
    };
}