listview+数据库+有网没网判断

package com.example.myapplication3.tab_Fragments;

import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.Toast;

import com.example.myapplication3.Bean;
import com.example.myapplication3.MyAdapter2;
import com.example.myapplication3.Myku.Dao;
import com.example.myapplication3.NetUtils;
import com.example.myapplication3.R;
import com.example.pulltolibrary.PullToRefreshBase;
import com.example.pulltolibrary.PullToRefreshListView;

import java.util.ArrayList;
import java.util.List;

public class Tab_Frangment01 extends Fragment {

    private String ApiUrl="http://www.xieast.com/api/news/news.php?page=";
    private int num=1;
    private PullToRefreshListView listview;
    private ArrayList<Bean.DataBean> list;
    private Dao dao;
    private MyAdapter2 myAdapter2;

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view=inflater.inflate(R.layout.tab_trangment01,container,false);

        listview = view.findViewById(R.id.pull_list);
        listview.setMode(PullToRefreshListView.Mode.BOTH);
        list = new ArrayList<>();
        dao = new Dao(getActivity());
        myAdapter2 = new MyAdapter2(getActivity(), list);
        listview.setAdapter(myAdapter2);
        initData(1);
        initLisnner();
        return view;
    }

    private void initData(int num) {

        if (NetUtils.panduan(getActivity())==false){
        Toast.makeText(getActivity(),"没网咯！",Toast.LENGTH_SHORT).show();
        list.addAll(dao.select());
        }else if (NetUtils.panduan(getActivity())==true){
        NetUtils.getInstance().RequestData1(ApiUrl + num, Bean.class, new NetUtils.CallBack<Bean>() {
                @Override
                public void onsuess(Bean b) {
                    //将数据添加到数据库
                    dao.delect();
                     for (int i=0;i<b.getData().size();i++){
                        dao.add(b.getData().get(i).getTitle(),b.getData().get(i).getThumbnail_pic_s(),b.getData().get(i).getThumbnail_pic_s02(),b.getData().get(i).getThumbnail_pic_s03());
                    }
                    list.addAll(dao.select());
                    myAdapter2.notifyDataSetChanged();
                    listview.onRefreshComplete();
                }
            });


        }

    }

    private void initLisnner() {

        listview.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ListView>() {
            @Override
            public void onPullDownToRefresh(PullToRefreshBase<ListView> refreshView) {

                num=1;
                list.clear();
                initData(num);
                myAdapter2.notifyDataSetChanged();
            }

            @Override
            public void onPullUpToRefresh(PullToRefreshBase<ListView> refreshView) {

                num++;
                initData(num);
                myAdapter2.notifyDataSetChanged();
            }
        });


    }
}