Android版本检测\自动更新

package com.hiyo.game.pdk.tool;  
import java.io.File;  
import java.io.FileOutputStream;  
import java.io.InputStream;  
import java.net.URL;  
import java.net.URLConnection;  
import android.app.Activity;  
import android.app.AlertDialog;  
import android.app.ProgressDialog;  
import android.content.Context;  
import android.content.DialogInterface;  
import android.content.Intent;  
import android.content.pm.PackageInfo;  
import android.content.pm.PackageManager.NameNotFoundException;  
import android.net.ConnectivityManager;  
import android.net.NetworkInfo;  
import android.net.Uri;  
import android.util.Log;  
import android.webkit.URLUtil;  
import com.hiyo.game.pdk.activity.R;  
/** 
 * Android AutoUpdate. 
 *  
 * lazybone/2010.08.20 
 *  
 * 1.Set apkUrl. 
 *  
 * 2.check(). 
 *  
 * 3.add delFile() method in resume()\onPause(). 
 */ 
public class MyAutoUpdate {  
    public Activity activity = null;  
    public int versionCode = 0;  
    public String versionName = "";  
    private static final String TAG = "AutoUpdate";  
    private String currentFilePath = "";  
    private String currentTempFilePath = "";  
    private String fileEx = "";  
    private String fileNa = "";  
    private String strURL = "http://127.0.0.1:81/ApiDemos.apk";  
    private ProgressDialog dialog;  
    public MyAutoUpdate(Activity activity) {  
        this.activity = activity;  
        getCurrentVersion();  
    }  
    public void check() {  
        if (isNetworkAvailable(this.activity) == false) {  
            return;  
        }  
        if (true) {// Check version.  
            showUpdateDialog();  
        }  
    }  
    public static boolean isNetworkAvailable(Context ctx) {