Android 程序自动更新

来源：互联网发布：python实现二叉树编辑：程序博客网时间：2024/06/04 18:30

之前帮别人定制的一个android应用需要加个自动更新的功能。在 Market 里的应用是无需操心此事的，但像我这种定制的程序就需要自己实现。

原理相当简单，检查更新的时候，通过指定的URL获取服务器端版本信息。比较版本，如果更新，访问服务器端返回的apk的URL地址，下载，安装。各种 Makert 也是通过类似的机制实现的。原理搞清楚了，代码就相当简单了。

获取apk的VesionName，即AndroidManifest.xml中定义的android:versionName

public String getVesionName(Context context)
{   String versionName = null;
   try {
       versionName = context.getPackageManager().getPackageInfo("net.vpntunnel", 0).versionName;
   } catch (NameNotFoundException e) {
       Log.e(TAG, e.getMessage());
   }

   return versionName;
}

更新以及安装程序需要的权限，在AndroidManifest.xml中添加

<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"></uses-permission>
<uses-permission android:name="android.permission.INSTALL_PACKAGES"></uses-permission>

获取apk的versionCode，即AndroidManifest.xml中定义的android:versionCode

public int getVersionCode(Context context) { int versionCode = 0; try { versionCode = context.getPackageManager().getPackageInfo("net.vpntunnel", 0).versionCode; } catch (NameNotFoundException e) { Log.e(TAG, e.getMessage()); } return versionCode; }

服务器端version.JSON，包含apk路径以及版本信息

{
    "ApkName":"NAME",
    "ApkFullName":"NAME_1.0.5.apk",
    "VersionName":"1.0.5",
    "VersionCode":3
}

获取远程服务器的版本信息

private void getRemoteJSON(string host) throws ClientProtocolException, IOException, JSONException {
   String url = String.format("http://%s/%s", host, VER_JSON);
   StringBuilder sb = new StringBuilder();
   HttpClient client = new DefaultHttpClient();
   HttpParams httpParams = client.getParams();
   HttpConnectionParams.setConnectionTimeout(httpParams, 3000);
   HttpConnectionParams.setSoTimeout(httpParams, 5000);
   HttpResponse response = client.execute(new HttpGet(url));
   HttpEntity entity = response.getEntity();
   if (entity != null) {
       BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"), 8192);

       String line = null;
       while ((line = reader.readLine()) != null) {
           sb.append(line + "\n");
       }
       reader.close();
   }

   JSONObject object = (JSONObject) new JSONTokener(sb.toString()).nextValue();
   this.apkFullName = object.getString("ApkFullName");
   this.versionName = object.getString("VersionName");
   this.versionCode = Integer.valueOf(object.getInt("VersionCode"));
}

发现更新的提醒窗口，通过AlertDialog实现

private void shoVersionUpdate(String newVersion, final String updateURL) {
   String message = String.format("%s: %s, %s", mContext.getString(R.string.found_newversion), newVersion, mContext.getString(R.string.need_update));
   AlertDialog dialog = new AlertDialog.Builder(mContext).setTitle(mContext.getString(R.string.alertdialog_title)).setMessage(message)
   // update
           .setPositiveButton(mContext.getString(R.string.alertdialog_update_button), new DialogInterface.OnClickListener() {
               @Override
               public void onClick(DialogInterface dialog, int which) {
                   pBar = new ProgressDialog(mContext);
                   pBar.setTitle(mContext.getString(R.string.progressdialog_title));
                   pBar.setMessage(mContext.getString(R.string.progressdialog_message));
                   pBar.setProgressStyle(ProgressDialog.STYLE_SPINNER);
                   dialog.dismiss();
                   downFile(updateURL);
               }
               // cancel
           }).setNegativeButton(mContext.getString(R.string.alertdialog_cancel_button), new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog, int whichButton) {
                   dialog.dismiss();
               }
           }).create();
   dialog.show();
}

下载新版的apk文件，存放地址可以放到SD卡中。通过Environment.getExternalStorageDirectory()获取SD卡中的路径

private void downFile(final String url) {
   pBar.show();
   new Thread() {
       public void run() {
           HttpClient client = new DefaultHttpClient();
           HttpGet get = new HttpGet(url);
           HttpResponse response;
           try {
               response = client.execute(get);
               HttpEntity entity = response.getEntity();
               long length = entity.getContentLength();
               InputStream is = entity.getContent();
               FileOutputStream fileOutputStream = null;
               if (is != null) {
                   File f = new File(UPDATE_DIR);
                   if (!f.exists()) {
                       f.mkdirs();
                   }
                   fileOutputStream = new FileOutputStream(new File(UPDATE_DIR, updateFileName));

                   byte[] buf = new byte[1024];
                   int ch = -1;
                   int count = 0;
                   while ((ch = is.read(buf)) != -1) {
                       fileOutputStream.write(buf, 0, ch);
                       count += ch;
                       Log.d(TAG, String.valueOf(count));
                       if (length > 0) {
                       }
                   }
               }
               fileOutputStream.flush();
               if (fileOutputStream != null) {
                   fileOutputStream.close();
               }

               handler.post(new Runnable() {
                   public void run() {
                       pBar.cancel();
                       installUpdate();
                   }
               });
           } catch (Exception e) {
               pBar.cancel();
               Log.e(TAG, e.getMessage());
           }
       }

   }.start();
}

安装更新

private void installUpdate() {
   Intent intent = new Intent(Intent.ACTION_VIEW);
   intent.setDataAndType(Uri.fromFile(new File(UPDATE_DIR, updateFileName)), "application/vnd.android.package-archive");
   mContext.startActivity(intent);
}

至此更新需要函数就完成了，根据自己的业务逻辑组合一下，更新功能就搞定了。也可以稍微封装下，写成一个通用类，下次就可以直接用了。