Android实现程序自动更新

package com.cloay.update;

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

/**
* 程序自动更新 UpdateTestActivity.java
*
* @author Cloay 2011-11-23
*/
public class UpdateTestActivity extends Activity {
private Button button;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

button = (Button) findViewById(R.id.check);
button.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
try {
checkVersion();
} catch (NameNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}

/**
* 检查是否需要更新程序
*
* @throws NameNotFoundException
*/
private void checkVersion() throws NameNotFoundException {
UpdateInfo updateInfo = new UpdateInfo();
URL url;
try {
url = new URL("http://localhost:8080/update.xml");
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
// connection.setConnectTimeout(5000);
updateInfo = ParseXmlUtils.parseXml(connection.getInputStream());

} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
if (updateInfo.getVersion().equals(VersionUtil.getVersionName(this))) {
Toast.makeText(this, "版本相同,不需要升级!", Toast.LENGTH_SHORT).show();
} else {
showUpdateDialog(updateInfo);
}
}

private void showUpdateDialog(UpdateInfo updateInfo) {
AlertDialog alertDialog = new AlertDialog.Builder(this)
.setTitle("提示检测到新版本,确定升级吗?").setIcon(R.drawable.ask)
.setMessage(updateInfo.getDescription())
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
})
.setNegativeButton("取消", new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
}).create();
alertDialog.show();
}
}

package com.cloay.update;

import java.io.IOException;
import java.io.InputStream;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
* 解析Xml文件 ParseXmlUtils.java
*
* @author Cloay 2011-11-7
*/
public class ParseXmlUtils {
/**
* 通过InputStream 解析文件
*
* @param in
* @return
*/
public static UpdateInfo parseXml(InputStream in) {
UpdateInfo updateInfo = new UpdateInfo();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = null;
try {
db = dbf.newDocumentBuilder();
Document doc = null;
doc = db.parse(in);
Element root = doc.getDocumentElement();
NodeList resultNode = root.getElementsByTagName("info");
for (int i = 0; i < resultnode.getlength();="" i++)="" {="" element="" res="(Element)" resultnode.item(i);="" updateinfo.setversion(res.getelementsbytagname("version")="" .item(0).getfirstchild().getnodevalue());="" updateinfo.seturl(res.getelementsbytagname("url").item(0)="" .getfirstchild().getnodevalue());="" updateinfo.setdescription(res="" .getelementsbytagname("description").item(0)="" .getfirstchild().getnodevalue());="" }="" }="" catch="" (parserconfigurationexception="" e)="" {="" e.printstacktrace();="" }="" catch="" (saxexception="" e)="" {="" e.printstacktrace();="" }="" catch="" (ioexception="" e)="" {="" e.printstacktrace();="" }="" return="" updateinfo;="" }="" }="">

package com.cloay.update;

/**
* 更新信息实体类 UpdateInfo.java
*
* @author Cloay 2011-11-23
*/
public class UpdateInfo {
private String version; // 版本号
private String url; // 新版本存放url路径
private String description; // 更新说明信息，比如新增什么功能特性等

public String getVersion() {
return version;
}

public void setVersion(String version) {
this.version = version;
}

public String getUrl() {
return url;
}

public void setUrl(String url) {
this.url = url;
}

public String getDescription() {
return description;
}

public void setDescription(String description) {
this.description = description;
}
}

package com.cloay.update;

import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;

/**
* 版本工具类 VersionUtil.java
*
* @author Cloay 2011-11-23
*/
public class VersionUtil {
/**
* 获取版本号
*
* @param context
*            上下文
* @return
* @throws NameNotFoundException
*/
public static String getVersionName(Context context)
throws NameNotFoundException {
// 获取PackageManager 实例
PackageManager packageManager = context.getPackageManager();
// 获得context所属类的包名，0表示获取版本信息
PackageInfo packageInfo = packageManager.getPackageInfo(
context.getPackageName(), 0);
return packageInfo.versionName;
}
}