Accelerometer Data Storing Code

i have downloaded this simple code and that i wanted the code to be modified so that it can store the accelerometer data to a .txt file or .csv file. i am very new to android programming and so i wanted to see how the coding first. Pls bear with my incapabilities. here is the code:

package com.example;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.view.Menu;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class MainActivity extends Activity implements SensorEventListener {
private SensorManager mSensorManager;
private Sensor mAccelerometer;

TextView title,tv,tv1,tv2;
RelativeLayout layout;


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

mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);

//get layout
layout = (RelativeLayout)findViewById(R.id.relative);

//get textviews
title=(TextView)findViewById(R.id.name);
tv=(TextView)findViewById(R.id.xval);
tv1=(TextView)findViewById(R.id.yval);
tv2=(TextView)findViewById(R.id.zval);


}

@Override
public final void onAccuracyChanged(Sensor sensor, int accuracy)
{
// Do something here if sensor accuracy changes.
}

@Override
public final void onSensorChanged(SensorEvent event)
{
// Many sensors return 3 values, one for each axis.
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];


//display values using TextView
title.setText(R.string.app_name);
tv.setText("X axis:" +"\t\t"+x);
tv1.setText("Y axis:" + "\t\t" +y);
tv2.setText("Z axis:" +"\t\t" +z);

}

@Override
protected void onResume()
{
super.onResume();
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}

@Override
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
}





i will be very glad to have a positive response to this thread.