does anyone know what how to use the "mId" variable in code provided by google?

<http://developer.android.com/guide/topics/ui/notifiers/notifications.html>

It is not explained in the documentation. but appears as the last line in the code. when am using this code it is undefined so I have to define it as this, "private int mId;"

totally lost on this one. the code where I got this is shown below.

mNotificationManager.notify(mId, mBuilder.build());

```
 ButtonOne.setOnClickListener(new View.OnClickListener() {

  private int mId;

// anonymous inner class override for on click
public void onClick(View v) {

    Intent myIntent = new Intent(MainActivity.this, CoverFlowExample.class);
     MainActivity.this.startActivity(myIntent);

     NotificationCompat.Builder mBuilder =
                new NotificationCompat.Builder(MainActivity.this)
                .setSmallIcon(R.drawable.ic_launcher)
                .setContentTitle("My notification")
                .setContentText("Hello World!");
        // Creates an explicit intent for an Activity in your app
        Intent resultIntent = new Intent(MainActivity.this, MainActivity.class);

        // The stack builder object will contain an artificial back stack for the
        // started Activity.
        // This ensures that navigating backward from the Activity leads out of
        // your application to the Home screen.
        TaskStackBuilder stackBuilder = TaskStackBuilder.create(MainActivity.this);
        // Adds the back stack for the Intent (but not the Intent itself)
        stackBuilder.addParentStack(MainActivity.class);
        // Adds the Intent that starts the Activity to the top of the stack
        stackBuilder.addNextIntent(resultIntent);
        PendingIntent resultPendingIntent =
                stackBuilder.getPendingIntent(
                    0,
                    PendingIntent.FLAG_UPDATE_CURRENT
                );
        mBuilder.setContentIntent(resultPendingIntent);
        NotificationManager mNotificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        // mId allows you to update the notification later on.
        mNotificationManager.notify(mId, mBuilder.build());

}

```

});