Exporting a SQLite database to an XML file in Android

Question

I know this is possible but I'm not really sure where to start. Has anyone been able to achieve this?

Thanks.

Answer 1

The DataXmlExporter class described in this article will export a SQL lite DB to an XML file.

http://www.screaming-penguin.com/node/7749

The full example is available in this SVN repo. The ManageData class invokes the export.

http://totsp.com/svn/repo/AndroidExamples/trunk/

You will need to create an application class that exposes the DB and referenced as the application name in the AndroidManifest.xml file. Then use that DB as the argument to the DataXmlExporter constructor.

Here's the application class I use. You should already have a class (probably not named DatabaseHelper) that extends SQLiteOpenHelper

package com.billybobbain.android.someapp;
import android.app.Application;
import android.util.Log;

public class MyApplication extends Application {

   public static final String APP_NAME = "SomeApp";  

   private DatabaseHelper dataHelper;   

   @Override
   public void onCreate() {
      super.onCreate();
      Log.d(APP_NAME, "APPLICATION onCreate");
      this.dataHelper = new DatabaseHelper(this);      
   }

   @Override
   public void onTerminate() {
      Log.d(APP_NAME, "APPLICATION onTerminate");      
      super.onTerminate();      
   }

   public DatabaseHelper getDataHelper() {
      return this.dataHelper;
   }

   public void setDataHelper(DatabaseHelper dataHelper) {
      this.dataHelper = dataHelper;
   }
}

Answer 2

Have a look at the source code here exporting-a-sqlite-database-to-an-xml-file-in-android

The only change I had to make (to stop a few Eclipse warnings) was to close a cursor in the exportData( ) method. To make the code more portable, I also passed the XML file and location as an argument rather then as a declared final field.

The code writes the XML file to the SD card. Now, @mmaitlen who listed the source code on his blog doesn't add in any features to test for the existence of an external storage unit. So that's left for you to do.

However, you can embed some simple code to test for the existence of a writeable memory card with the following snippet (untested):

    sdOkToWrite = false;
    String sdTest = Environment.getExternalStorageState();
    if (sdTest.equals(Environment.MEDIA_MOUNTED)) {
        sdOkToWrite = true;
    } else {
    // Here's where you can code what to do without the external storage
    }

Testing for the external storage is useful if you have large files to create that may exceed internal capacity.