pullTofresh+AsynTask_515mapp下载-优快云博客

本文介绍了一个基于 Android 的 Pull-to-Refresh ListView 控件实现案例。通过使用 PullToRefreshListView 和 AsyncTask，实现了下拉刷新和上拉加载更多功能，并展示了如何通过自定义适配器显示数据。
摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >
layout_main
----------------------------------------------------------------------------
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.pulltorefrsh.MainActivity">

<com.handmark.pulltorefresh.library.PullToRefreshListView
    android:id="@+id/grid"
    android:layout_width="400dp"
    android:layout_height="400dp"
    android:cacheColorHint="#000000"
    android:divider="#19000000"
    android:dividerHeight="4dp"
    android:fadingEdge="none"
    android:fastScrollEnabled="false"
    android:footerDividersEnabled="false"
    android:headerDividersEnabled="false"
    android:smoothScrollbar="true"
     />
</android.support.constraint.ConstraintLayout>

MainActivity
---------------------------------------------------------------------------

package com.example.pulltorefrsh;
import android.app.AlertDlog;//ialog;import android.os.AsyncTask;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.google.gson.Gson;
import com.handmark.pulltorefresh.library.PullToRefreshBase;
import com.handmark.pulltorefresh.library.PullToRefreshGridView;
import com.example.pulltorefrsh.Bean.ResultBean.RowsBean;
import com.handmark.pulltorefresh.library.PullToRefreshListView;
import com.nostra13.universalimageloader.core.ImageLoader;

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

public class MainActivity extends AppCompatActivity {
    String url = "http://api.fang.anjuke.com/m/android/1.3/shouye/recInfosV3/?city_id=14&lat=40.04652&lng=116.306033&api_key=androidkey&sig=9317e9634b5fbc16078ab07abb6661c5&macid=45cd2478331b184ff0e15f29aaa89e3e&app=a-ajk&_pid=11738&o=PE-TL10-user+4.4.2+HuaweiPE-TL10+CHNC00B260+ota-rel-keys%2Crelease-keys&from=mobile&m=Android-PE-TL10&cv=9.5.1&cid=14&i=864601026706713&v=4.4.2&pm=b61&uuid=1848c59c-185d-48d9-b0e9-782016041109&_chat_id=0&qtime=20160411091603";
    String urlimg = "http://pic2.ajkimg.com/display/xinfang/9b4c133d2c5528a45cb26976d515d104/275x206n.jpg";
    private PullToRefreshListView grid;
    private ImageLoader instance;
    List<RowsBean> list = new ArrayList<RowsBean>();
    private Myadapter myadapter = new Myadapter();
    private ListView listView;
    private int type = 10;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        instance = ImageLoader.getInstance();
        grid = (PullToRefreshListView) findViewById(R.id.grid);
        grid.setMode(PullToRefreshBase.Mode.BOTH);
        grid.setRefreshing(true);
        listView = grid.getRefreshableView();
        dask();
        listView.setAdapter(myadapter);
        grid.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ListView>() {
            @Override
            public void onPullDownToRefresh(PullToRefreshBase<ListView> pullToRefreshBase) {
                new myAsyn().execute(url);
            }

            @Override
            public void onPullUpToRefresh(PullToRefreshBase<ListView> pullToRefreshBase) {
                new myAsyn2().execute(url);
            }
        });
    }

    private void dask() {
        new myAsyn().execute(url);
    }

    private class Myadapter extends BaseAdapter {
        @Override
        public int getCount() {
            return list.size();
        }

        @Override
        public Object getItem(int position) {
            return list.get(position);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = View.inflate(MainActivity.this, R.layout.list_item, null);
            }
            TextView tv1 = convertView.findViewById(R.id.tv);
            ImageView iv = convertView.findViewById(R.id.iv);
            tv1.setText(list.get(position).getInfo().getFang_type());
            instance.displayImage(urlimg, iv);
            return convertView;
        }
    }

    private class myAsyn extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... strings) {
            Log.e("GetJson", "" + Util.getJson(url));
            return Util.getJson(strings[0]);
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            Gson gson = new Gson();
            Bean bean = gson.fromJson(s, Bean.class);
            Bean.ResultBean resultBean = bean.getResult();
            List<RowsBean> rows = resultBean.getRows();
            list.addAll(rows);
            listView.setAdapter(myadapter);
            Toast.makeText(getApplication(), list.get(0).getInfo().toString(), Toast.LENGTH_LONG).show();
            myadapter.notifyDataSetChanged();
            grid.onRefreshComplete();
        }
    }

    private class myAsyn2 extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... strings) {
            return Util.getJson(strings[0]);
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            list.clear();
            Gson gson = new Gson();
            Bean bean = gson.fromJson(s, Bean.class);
            Bean.ResultBean resultBean = bean.getResult();
            List<RowsBean> rows = resultBean.getRows();
            list.addAll(rows);
            Toast.makeText(getApplication(), list.get(0).getInfo().getHas_quanjing(), Toast.LENGTH_LONG).show();
            listView.setAdapter(myadapter);
            grid.onRefreshComplete();
            myadapter.notifyDataSetChanged();
        }
    }
}

Mapp类
-------------------------------------------------------------
package com.example.pulltorefrsh;

import android.app.Application;

import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;

/**
 * Created by Administrator on 2017/11/17 0017.
 */

public class Mapp extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        ImageLoaderConfiguration build = new ImageLoaderConfiguration.Builder(this).build();
        ImageLoader.getInstance().init(build);
    }
}

Util类
 -----------------------------------------------------------------------------------
package com.example.pulltorefrsh;

import android.util.Log;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

/**
 * Created by Administrator on 2017/11/17 0017.
 */

public class Util {
   public static String getJson(String url)
    {
        StringBuffer sb = new StringBuffer();
        try {
            URL url1 = new URL(url);
            HttpURLConnection urlConnection = (HttpURLConnection) url1.openConnection();
            int responseCode = urlConnection.getResponseCode();
//            if(responseCode==200) {
            InputStream inputStream = urlConnection.getInputStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(inputStream,"utf-8"));
                String len = "";
                while ((len = br.readLine()) != null) {
                    sb.append(len);
                }
//            }else{
//                Log.e("util","++++++++++无网络+++++++++++++++");
//            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return sb.toString();
    }
}

bean类
从统一资源定位器获取json，studio的gsonfrment控件生成、

权限
----------------------------------------------------------
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
依赖
-----------------------------------------------------------------------
implementation 'com.google.code.gson:gson:2.2.4'
compile 'com.nostra13.universalimageloader:universal-image-loader:1.9.5'
compile 'com.github.userswlwork:pull-to-refresh:1.0.0'