A very basic (no real error handling / tag formatting etc) example of writing Android Application Records

AAR Example.java

public void onNewIntent(Intent intent) 
{
	Tag tagFromIntent = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
	WriteTag(tagFromIntent);
}

public void WriteTag(final Tag receivedTag)
{
	((Thread) new Thread()
	{
		public void run()
		{	
			NdefRecord aaRecord = NdefRecord.createApplicationRecord("io.d0");
			NdefRecord idRecord = NdefRecord.createExternal("io.d0:tag", Integer.toString(tagType), tagMetaData.toString().getBytes(Charset.forName("US-ASCII")));

			try
  			{
				thisNdef = Ndef.get(receivedTag);
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
        
			if(thisNdef.isWritable())
  			{
          			NdefMessage tagMsg = new NdefMessage(new NdefRecord[]{idRecord,aaRecord});
				thisNdef.writeNdefMessage(tagMsg);
				thisNdef.makeReadOnly();
				thisNdef.close();
  			}
		}
	}).start();
}