handler三秒轮播数据

//activity_main

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="animtest.com.example.e531.week1_10month.MainActivity">    <TextView        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Hello World!"        android:id="@+id/tv_news"/>    <ListView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/lv"        android:layout_below="@+id/tv_news">    </ListView></RelativeLayout>

//item.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <ImageView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/img"/>    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/tv_title"/>    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/tv_date"/></LinearLayout>

//MainActivity

package animtest.com.example.e531.week1_10month;import android.os.AsyncTask;import android.os.Message;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.ImageView;import android.widget.ListView;import android.widget.TextView;import com.google.gson.Gson;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.client.HttpClient;import org.apache.http.client.methods.HttpGet;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.util.EntityUtils;import org.json.JSONArray;import org.json.JSONException;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.UnsupportedEncodingException;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.util.ArrayList;import java.util.List;import java.util.logging.Handler;import java.util.logging.LogRecord;public class MainActivity extends AppCompatActivity {    private TextView tv;    private ListView lv;    private List<String> datas=new ArrayList<String>();    private List<News> newDatas;    private int index=0;    private android.os.Handler myHandler=new android.os.Handler(){        @Override        public void handleMessage(Message msg) {            tv.setText(datas.get(index%datas.size()));            index++;            //延迟3秒再次发送消息            sendEmptyMessageDelayed(1,3000);        }    };    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tv=(TextView) findViewById(R.id.tv_news);        lv= (ListView) findViewById(R.id.lv);        //开启一个了线程        new Thread(){            @Override            public void run() {                try {                    //1.创建URL                    URL url=new URL("http://www.toutiao.com/hot_words/");                    //2.打开连接,进行请求                    HttpURLConnection connection= (HttpURLConnection) url.openConnection();                    //3.设置                    connection.setRequestMethod("GET");                    connection.setReadTimeout(5000);                    connection.setConnectTimeout(5000);                    //4.判断响应码                    if(connection.getResponseCode()==200){                        //5.得到返回结果                        InputStream stream=connection.getInputStream();                        //将流转换成字符串                        String str=streamToString(stream);                        //进行解析                        getJsonData(str);                        //发送一个空消息                        myHandler.sendEmptyMessage(1);                    }                } catch (MalformedURLException e) {                    e.printStackTrace();                } catch (IOException e) {                    e.printStackTrace();                }            }        }.start();    }     public  void getJsonData(String str){         try {             //Gson  原生解析             JSONArray array=new JSONArray(str);             for(int i=0;i<array.length();i++){                 String data=array.optString(i);                 datas.add(data);             }         } catch (JSONException e) {             e.printStackTrace();         }     }     public String streamToString(InputStream inputStream){         StringBuilder builder=new StringBuilder();         try {             BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(inputStream,"utf-8"));             String con;             while ((con=bufferedReader.readLine())!=null){                 builder.append(con);             }         } catch (UnsupportedEncodingException e) {             e.printStackTrace();         } catch (IOException e) {             e.printStackTrace();         }         return builder.toString();     }    class MyTask extends AsyncTask<String,Void,String> {        @Override        protected String doInBackground(String... params) {            //1.创建httpClient            HttpClient htttpClient=new DefaultHttpClient();            //2.创建httpget            HttpGet httpGet=new HttpGet(params[0]);            try {                 //3.执行请求                HttpResponse response=htttpClient.execute(httpGet);                //4.判断响应吗                if(response.getStatusLine().getStatusCode()==200){                    //5得到结果                    HttpEntity entity=response.getEntity();                    //6.将结果转换为String                    return EntityUtils.toString(entity);                }            } catch (IOException e) {                e.printStackTrace();            }            return null;        }        @Override        protected void onPostExecute(String s) {            super.onPostExecute(s);            //使用gson 进行解析            Gson gson=new Gson();            Result result=gson.fromJson(s,Result.class);            Log.d("zzz",result.toString());             newDatas=result.getNewslist();            //显在listView列表            lv.setAdapter(new MyAdapter());        }    }    class  MyAdapter extends BaseAdapter{        @Override        public int getCount() {            return newDatas.size();        }        @Override        public Object getItem(int position) {            return null;        }        @Override        public View getView(int position, View convertView, ViewGroup parent) {            ViewHolder holder;            if(convertView==null){                convertView=View.inflate(MainActivity.this,R.layout.item,null);                holder=new ViewHolder();                holder.tvTitle= (TextView) convertView.findViewById(R.id.tv_title);                holder.tvDate= (TextView) convertView.findViewById(R.id.tv_date);                holder.imageView=(ImageView) convertView.findViewById(R.id.img);                convertView.setTag(holder);            }else{                holder=(ViewHolder) convertView.getTag();            }            holder.tvTitle.setText(newDatas.get(position).getTitle());            holder.tvDate.setText(newDatas.get(position).getCtime());            return convertView;        }        @Override        public long getItemId(int position) {            return 0;        }        class ViewHolder{            TextView tvTitle;            TextView tvDate;            ImageView imageView;        }    }}

//News

package animtest.com.example.e531.week1_10month;/** * Created by e531 on 2017/10/10. */public class News {    private String title;    private String ctime;    private String picUrl;    @Override    public String toString() {        return "News{" +                "title='" + title + '\'' +                ", ctime='" + ctime + '\'' +                ", picUrl='" + picUrl + '\'' +                '}';    }    public String getTitle() {        return title;    }    public void setTitle(String title) {        this.title = title;    }    public String getCtime() {        return ctime;    }    public void setCtime(String ctime) {        this.ctime = ctime;    }    public String getPicUrl() {        return picUrl;    }    public void setPicUrl(String picUrl) {        this.picUrl = picUrl;    }}

//Result

package animtest.com.example.e531.week1_10month;import java.util.List;/** * Created by e531 on 2017/10/10. */public class Result {    private List<News> newslist;    public List<News> getNewslist() {        return newslist;    }    public void setNewslist(List<News> newslist) {        this.newslist = newslist;    }    @Override    public String toString() {        return "Result{" +                "newslist=" + newslist +                '}';    }}