android Handler okhttp

package com.example.mepositry.fragment;

import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

import com.example.mepositry.R;
import com.example.mepositry.bean.AdBean;
import com.google.gson.Gson;

import java.io.IOException;
import java.util.List;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class EntertainmentFragment extends Fragment {
    private String mUrl2 = "http://test/api/po/hg";
    private OkHttpClient mOkHttpClient;
    private Button btn;

    final Handler handler = new Handler(Looper.getMainLooper()) {
        @Override
        public void handleMessage(Message msg) {
            String stringJson = (String) msg.obj;
            Gson gson = new Gson();
            AdBean mAdBean = gson.fromJson(stringJson, AdBean.class);
            List<AdBean.DataBean> list = mAdBean.getData();
            System.out.println(list);
        }
    };

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_entertainment, container, false);

        btn = view.findViewById(R.id.btn);
        mOkHttpClient = new OkHttpClient();
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                updateWeatherDataCoordinates();
            }
        });
        return view;
    }

    public void updateWeatherDataCoordinates() {
        Request request = new Request.Builder()
                .url(mUrl2)
                .build();
        mOkHttpClient.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                Log.e("TAG", "onFailure");
            }

            @Override
            public void onResponse(Call call, final Response response) throws IOException {
                final String stringJson = response.body().string();
                Log.e("TAG", "GetActivity2_onResponse" + stringJson);

                Message msg = new Message();
                msg.obj = stringJson;
                handler.sendMessage(msg);

            }
        });
    }
}

  <com.google.android.material.tabs.TabLayout
        android:id="@+id/main_tablayout"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:textSize="15sp"
        app:tabBackground="@color/blue"
        app:tabIndicatorColor="@color/orange"
        app:tabIndicatorHeight="2dp"
        app:tabMode="auto"
        app:tabSelectedTextColor="@color/red"
        app:tabTextColor="@color/white" />