NFC

 Near Filed Communication  Is a short range high frequency wireless communication technology  Low speed (106 to 424 kbps)  Low friction setup (no discovery, no pairing)  NFC is an extension of Radio frequency identification (RFID) technology - RFID is mainly used for tracking and identification by sending radio waves 2 What is NFC?

How NFC works? Use NFC to read information from a tag Use NFC to read peer to peer information

How NFC is used with Android?  NFC feature is available from Android 2.3 version  Android Ice Cream Sandwich 4.0 introduced a new peer-to-peer interaction model 0-click contact sharing 0-click web page sharing 0-click youtube video sharing

How to NFC? Reading NDEF data from an NFC tag = Nfc Data Exchange Format  By design, NDEF data is dispatched to only one activity  The type of the first NDEF record is used for dispatch  The data container format for NFC More on

Reading NDEF data Different Dispatch Types

Reading NDEF data  Android Manifest  Activity class protected void onResume() { … if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) { NdefMessage[] messages = getNdefMessages(getIntent()); byte[] payload = messages[0].getRecords()[0].getPayload(); … } How to use NFC reading within Java code

Writing NDEF data Writing NDEF tags String text; NdefRecord textRecord = new NdefRecord(NdefRecord.TNF_MIME_MEDIA,"text/plain".getBytes(), text.getBytes()); NdefMessage textMessage = new NdefMessage(new NdefRecord[]{textRecord}); Tag tag = getIntent().getExtra(NfcAdapter.EXTRA_TAG); Ndef ndef = Ndef.get(tag); ndef.writeNdefMessage(textMessage);

Writing Peer to Peer  Foreground Activities can register an NDEF payload for P2P push Register the payload in advance adapter.enableForegroundNdefPush(this, ndefMessage);  Ice Cream Sandwich preview Register interest in P2P in advance, push the payload live public interface NdefPushCallback { public NdefMessage createMessage(); } adapter.registerForegroundNdefPush(this, callback); Writing NDEF data

Sources e.com/en//events/io/2011/static/presofiles/how_to_nfc.pdf

Questions & (hopefully) Answers String question = audience.getNextQuestion(); while (question != null && timeLeft.getValue() > 0) { try { answer(question); } catch (AnswerNotKnownException e) { MakeSomethingUp(); LOG.warn("Missed one: " + question, e); } question = audience.getNextQuestion(); timeLeft.update(); } audience.thankForAttention();