Android news browsing client based on PHP background, php background android news

The example in this article shares with you the Android news browsing client, based on php background, for your reference, specific The content is as follows

1. Use HBuilder to configure the PHP environment and test whether the MySQL statement can be queried. This has been explained in detail before.

2. Here the php background implements the query function of mysql and returns a client in JSON data format

Create a mysql_connect.php file here in PHP to connect to the database and set the character set format.

<&#63;php

$con = mysql_connect("localhost","root","123456");
//設(shè)置字符集為UTF-8 可解決中文亂碼
mysql_query("SET NAMES 'utf8'");
mysql_query("SET CHARACTER SET utf8");
mysql_query("SET CHARACTER_SET_RESULT=utf8");

if(!$con){
die(mysql_error());
}

mysql_select_db("newsdemo",$con);
&#63;>

Then create a new getNewsJSON.php file to convert the query results into JSON string format. Only the json_encode method is needed.

<&#63;php

/*獲得JSON數(shù)據(jù)
 * 返回值：title desc time content_url pic_url*/ 
 
 require 'mysql_connect.php';

$n = 0;
$result = mysql_query("select * from news");
while($row = mysql_fetch_array($result)){
$arr[$n++] = array(
"title"=>$row['title'],
"desc"=>$row['desc'],
"time"=>$row['time'],
"content_url"=>$row['content_url'],
"pic_url"=>$row['pic_url']
);
}

//數(shù)組轉(zhuǎn)化為JSON字符串
echo json_encode($arr);
&#63;>

The focus is on the design and development of the Android side

1. Design interface

Since the same format needs to be set in each Item of the ListView, the ListView Adapter is used here

Add a ListView control in the main interface LinearLayout

2. Mainactivity program is as follows:

public class MainActivity extends Activity implements OnItemClickListener{


  private ListView lvNews ;
  private NewsAdapter adapter ;
  //定義集合
  private List<News> newsList ;
  
  //獲取json字符串的URL地址
  public static final String GET_NEWS_URL = "http://211.87.234.20/NewsDemo/getNewsJSON.php";

  //獲取msg之后如何處理
  private Handler getNewsHandler = new Handler(){
  public void handleMessage(android.os.Message msg){
  String jsonData = (String) msg.obj ;
  System.out.println(jsonData) ;
  try {
JSONArray jsonArray = new JSONArray(jsonData) ;
for(int i=0;i<jsonArray.length();i++){
JSONObject object = jsonArray.getJSONObject(i) ;
String title = object.getString("title") ;
String desc = object.getString("desc") ;
String time = object.getString("time") ;
String content_url = object.getString("content_url") ;
String pic_url = object.getString("pic_url") ;
System.out.println("title="+title) ;
//add一個(gè)News類型的Object
newsList.add(new News(title,desc,time,content_url,pic_url)) ;
}
//通知更新
adapter.notifyDataSetChanged() ;
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
  
  } ;
  } ;
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState) ;
    setContentView(R.layout.activity_main) ;
    
    lvNews = (ListView) findViewById(R.id.lvNews) ;
    //初始化
    newsList = new ArrayList<News>();  
    adapter = new NewsAdapter(this,newsList) ;
    lvNews.setAdapter(adapter) ;
    lvNews.setOnItemClickListener(this) ;
    
    HttpUtils.getNewsJSON(GET_NEWS_URL,getNewsHandler) ;
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
  }

@Override
public void onItemClick(AdapterView<&#63;> arg0, View arg1, int position, long arg3) {
// TODO Auto-generated method stub
News news = newsList.get(position) ;
Intent intent = new Intent(this,BrowseNewsActivity.class) ;
intent.putExtra("content_url",news.getContent_url()) ;
startActivity(intent) ;
}
  
}

A tool class HttpUtils and a custom NewsAdapter are needed here to realize the view display of the item.

HttpUtils code is as follows:

package com.MR.news.utils;



import java.io.BufferedReader;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.HttpURLConnection;

import java.net.URL;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.os.Handler;

import android.os.Message;

import android.widget.ImageView;



public class HttpUtils {



//工具類直接定義成靜態(tài)方法即可

/*url用于內(nèi)部類中，所以要將其設(shè)定為final類型*/

/*讀取完成需要通知主線程，需要使用handler*/

public static void getNewsJSON(final String url,final Handler handler){

//訪問網(wǎng)絡(luò)，時(shí)間長(zhǎng)，開啟新線程

new Thread(new Runnable(){



@Override

public void run() {

// TODO Auto-generated method stub

HttpURLConnection conn ;

InputStream is ;

try {

conn = (HttpURLConnection) new URL(url).openConnection() ;

//GET方式獲取

conn.setRequestMethod("GET") ;

//得到輸入流

is=conn.getInputStream() ;

//讀取數(shù)據(jù)用緩沖,里面要傳入一個(gè)reader

BufferedReader reader = new BufferedReader(new InputStreamReader(is));

//一行一行讀取數(shù)據(jù)

String line = "";

//沒讀完一行進(jìn)行拼接,高效

StringBuilder result = new StringBuilder();

while((line = reader.readLine()) != null){

result.append(line);

}

Message msg = new Message() ;

//msg.obj可以放進(jìn)去任何對(duì)象

msg.obj = result.toString() ;

handler.sendMessage(msg) ;

} catch (Exception e) {

e.printStackTrace();

}

}}).start() ;

}



public static void setPicBitMap(final ImageView ivPic,final String pic_url){

new Thread(new Runnable(){



@Override

public void run() {

// TODO Auto-generated method stub

try {

HttpURLConnection conn = (HttpURLConnection) new URL(pic_url).openConnection() ;

conn.connect() ;

InputStream is = conn.getInputStream() ;

//bitmap就是所需圖片資源

/*從資源文件中的到圖片*/

Bitmap bitmap = BitmapFactory.decodeStream(is) ;

ivPic.setImageBitmap(bitmap) ;

is.close() ;

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

} 



}



}).start() ;

}

}

NewsAdapter code is as follows:

package com.MR.news.adapter;



import java.util.List;

import com.MR.news.R;

import com.MR.news.model.News;

import com.MR.news.utils.HttpUtils;

import android.content.Context;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.ImageView;

import android.widget.TextView;



public class NewsAdapter extends BaseAdapter {





//聲明上下文對(duì)象，后面的getView方法需要

private Context context;

private List<News> newsList;



public NewsAdapter(Context context, List<News> newsList){

this.context = context ;

this.newsList = newsList ;

}

@Override

public int getCount() {

// TODO Auto-generated method stub

return newsList.size();

}

@Override

public Object getItem(int position) {

// TODO Auto-generated method stub

return newsList.get(position);

}

@Override

public long getItemId(int position) {

// TODO Auto-generated method stub

return position;

}

@Override

public View getView(int position, View convertView, ViewGroup arg2) {

// TODO Auto-generated method stub

if(convertView == null){

convertView = LayoutInflater.from(context).inflate(R.layout.news_item,null) ;

}

TextView tvTitle = (TextView) convertView.findViewById(R.id.tvTitle) ;

TextView tvDesc = (TextView) convertView.findViewById(R.id.tvDesc) ;

TextView tvTime = (TextView) convertView.findViewById(R.id.tvTime) ;

ImageView ivPic = (ImageView) convertView.findViewById(R.id.ivPic);



News news = newsList.get(position) ;

tvTitle.setText(news.getTitle()) ;

tvDesc.setText(news.getDesc()) ;

tvTime.setText(news.getTime()) ;



String pic_url = news.getPic_url() ;

HttpUtils.setPicBitMap(ivPic, pic_url) ;



return convertView;

}





}

news_item is used to set the display format of each item

<&#63;xml version="1.0" encoding="utf-8"&#63;>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent" >
  
  <ImageView 
    android:id="@+id/ivPic"
    android:layout_width="42dp"
    android:layout_height="42dp"
    android:src="@drawable/ic_launcher"
    />

  <TextView
    android:id="@+id/tvTitle"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@+id/ivPic"
    android:text="title"
    android:textSize="18sp" />

  <TextView
    android:id="@+id/tvDesc"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/tvTitle"
    android:layout_below="@+id/tvTitle"
    android:text="desc"
    android:textSize="18sp" />
  <TextView
    android:id="@+id/tvTime"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentRight="true"
    android:text="time"
    android:textSize="10sp"
    />

</RelativeLayout>

Note: This item needs to display a single image, so the Bitmap class is used. Since network transmission is used, the concept of threads needs to be used! !

The key is to understand the relationship between handler message and loop.

The above is the entire content of this article. I hope it will be helpful to everyone in learning Android software programming.