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本文實(shí)例為大家分享了Android新聞瀏覽客戶端，基于php后臺，供大家參考，具體內(nèi)容如下

1、使用HBuilder進(jìn)行PHP環(huán)境配置，測試是否可以查詢MySQL語句，之前都已經(jīng)詳細(xì)說明過了。

2、此處php后臺實(shí)現(xiàn)mysql的查詢功能，并以JSON數(shù)據(jù)格式返回個(gè)客戶端

在PHP此處建立一個(gè)mysql_connect.php文件，實(shí)現(xiàn)數(shù)據(jù)庫的連接，并設(shè)置字符集格式。

<?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);

?>

然后新建一個(gè)getNewsJSON.php文件用于進(jìn)行將查詢結(jié)果轉(zhuǎn)換成JSON字符串格式。只需要 json_encode這個(gè)方法即可。

<?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);

?>

重點(diǎn)在于Android端的設(shè)計(jì)開發(fā)

1、設(shè)計(jì)界面

由于需要以在ListView的每個(gè)Item中設(shè)置相同的格式，所以此處運(yùn)用ListView+Adapter的形式

在主界面LinearLayout中添加一個(gè)ListView控件

2、Mainactivity程序如下：

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<?> 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) ;

}

}

此處需要一個(gè)工具類HttpUtils以及自定義的NewsAdapter以實(shí)現(xiàn)item的視圖顯示.

HttpUtils代碼如下：

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，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代碼如下：

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用來設(shè)置每個(gè)item的顯示格式

<?xml version="1.0" encoding="utf-8"?>

<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>

注意：此item中需要顯示單個(gè)圖片，所以用到Bitmap這個(gè)類。由于用到網(wǎng)絡(luò)傳輸，所以需要用到線程這個(gè)概念??！

關(guān)鍵理解handler message以及l(fā)oop這三者的關(guān)系。

以上就是本文的全部內(nèi)容，希望對大家學(xué)習(xí)Android軟件編程有所幫助。