Android studio请求网络数据ListView异步加载展示文字条目 ImageLoadler加载图片

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主函数布局是一个ListView

item布局是TextView和ImageView 数量的多少视情况而定

再写一个网络请求数据的类最后面有代码： ”urlConnection 请求数据类的封装“

类名一定要一样

封装数据类还有别忘了依赖和权限

依赖：

imageloader compile ‘com.nostra13.universalimageloader:universal-image-loader:1.9.5’

gson compile 'com.google.code.gson:gson:2.6.2'

Tablayout compile 'com.android.support:design:26+'

pulltorefresh compile 'com.android.support:support-v4:23.3.0' 或 compile 'com.github.userswlwork:pull-to-refresh:1.0.0'

Banner无限轮播 compile 'com.youth.banner:banner:1.4.9'

权限：

<uses-permission android:name="android.permission.INTERNET" /><uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/><uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/><uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

主页面 MainActivity
package com.example.myapplication;import android.graphics.Bitmap;import android.os.AsyncTask;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.util.Log;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.ListView;import android.widget.TextView;import com.google.gson.Gson;import com.nostra13.universalimageloader.core.DisplayImageOptions;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.assist.ImageScaleType;import java.util.List;public class MainActivity extends AppCompatActivity {    private ListView lv;    String urlTotal = "https://api.tianapi.com/wxnew/?key=8d6e3228d25298f13af4fc40ce6c9679&num=10&page=1";    private MAdapter mAdapter;    private List<News.NewslistBean> list;    private String imageUrl="";    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        lv = (ListView) findViewById(R.id.lv);        initData();    }    private void initData() {        new MJsonAsyncTask().execute(urlTotal);    }    class MJsonAsyncTask extends AsyncTask<String, Void, String> {        public MJsonAsyncTask() {            super();        }        //主线程可以更新ui        @Override        protected void onPostExecute(String s) {            super.onPostExecute(s);            News news = new Gson().fromJson(s, News.class);            list = news.getNewslist();            mAdapter = new MAdapter();            lv.setAdapter(mAdapter);        }        //这个回调方法是子线程;        @Override        protected String doInBackground(String... strings) {            //取第0个元素,就是url;            String netjson = NetWordUtils.getNetjson(strings[0]);//调用网络请求工具类            return netjson;        }    }    class MAdapter extends BaseAdapter {        @Override        public int getCount() {            return list.size();        }        @Override        public Object getItem(int i) {            return list.get(i);        }        @Override        public long getItemId(int i) {            return i;        }        @Override        public View getView(int i, View containerView, ViewGroup viewGroup) {            View view = View.inflate(MainActivity.this, R.layout.item, null);            TextView tv_name = (TextView) view.findViewById(R.id.tv);            ImageView iv = (ImageView) view.findViewById(R.id.iv);            tv_name.setText(list.get(i).getTitle());            /**             * getView方法每个条目显示的时候都会调用,所以我们在这个请求图片,并设置             *  把图片url传递给asyncTask             */            //new MAsyncTaskImage(iv).execute(list.get(i).getPicUrl());            ImageLoader.getInstance().displayImage(list.get(i).getPicUrl(),iv);        //    Log.d("wyy",list.get(i).getPicUrl());            return view;        }    }}

mapp类（清单文件中记得写name=".mapp"）;
package com.example.myapplication;import android.app.Application;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;/** * Created by DELL- on 2017/11/6. */public class mapp extends Application {    @Override    public void onCreate() {        super.onCreate();        ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(this).build();//开始构建        ImageLoader.getInstance().init(config);//全局初始化此配置    }}
清单文件：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.myapplication">    <uses-permission android:name="android.permission.INTERNET" />    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>    <application        android:name=".mapp"        android:allowBackup="true" android:icon="@mipmap/ic_launcher"        android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true" android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>

NetWordUtils类（工具类）

package com.example.myapplication;import android.graphics.Bitmap;import android.graphics.BitmapFactory;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;/** *  2017-09-27. */public class NetWordUtils {    private static String  tag = "NetWordUtils";    /**     * 获取网络json     *     * @param urlString     * @return     */    public static String getNetjson(String urlString) {        try {            URL url = new URL(urlString);            HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();            urlConnection.setRequestMethod("GET");//若果是get请求可以不用配置; 其他请求必须配置            urlConnection.setConnectTimeout(8000);//设置链接超时间            InputStream inputStream = urlConnection.getInputStream();//获取网络返回的输入流;            //可拼接的字符串            StringBuilder stringBuilder = new StringBuilder();            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));            String temp = "";            while ((temp = bufferedReader.readLine()) != null) {                stringBuilder.append(temp);                temp = "";            }            //这个是网络获取的数据            String data = stringBuilder.toString();            Log.e(tag, "getData: " + data);            return data;        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }        return "";    }}

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