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NFC. 2. What is NFC?. N ear F iled C ommunication 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
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2 What is 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
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 http://developer.android.com/reference/android/nfc/NdefMessage.html http://developer.android.com/reference/android/nfc/NdefRecord.html
Reading NDEF data Different Dispatch Types
Reading NDEF data How to use NFC reading within Java code • Android Manifest <intent-filter> <action android:name="android.nfc.action.NDEF_DISCOVERED"/> <categoryandroid:name="android.intent.category.DEFAULT"/> <dataandroid:mimeType="text/plain"/> </intent-filter> • Activity class onResume @Override protectedvoid onResume() { … if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) { NdefMessage[] messages = getNdefMessages(getIntent()); byte[] payload = messages[0].getRecords()[0].getPayload(); … }
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 NDEF data 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);
Sources http://developer.android.com/guide/topics/connectivity/nfc/nfc.html#tag-dispatch http://static.googleusercontent.com/external_content/untrusted_dlcp/www.google.com/en//events/io/2011/static/presofiles/how_to_nfc.pdf http://www.jessechen.net/blog/how-to-nfc-on-the-android-platform/ http://developer.android.com/reference/android/nfc/package-summary.html
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