Send a url between 2 NFC devices

Question

I have an android application with a webview in it.
When the webview is getting to url with certain text, e.g. ticket, then I would like to send the url to another NFC device through NFC.
I was able to send the url to the type 4 NFC tag, but I am not able to find out how to send it to other NFC device so that it will launch the browser with the url.
I was just using the following to create the NDEF

NdefRecord uriRecord = NdefRecord.createUri(url);
NdefMessage message = new NdefMessage(new NdefRecord[] {
            uriRecord            
});

and then use this to write

ndef.writeNdefMessage(message);

I am writing the app in ICS (on galaxy nexus) and trying to send to the galaxy s2 with 2.3.6.

Any help and pointer will be appreciated.

does galaxy s2 have NFC chip? – Ethan Liou Mar 20 '12 at 18:18 — Ethan Liou, Mar 20 '12 at 18:18
yes, it does, I was able to read a nfc tag on galaxy s2 – DaiLak Mar 20 '12 at 18:52 — DaiLak, Mar 20 '12 at 18:52

score 2 · Accepted Answer · edited Jan 09 '14 at 23:48

2

When sending an NDEF message to another phone, you don't use a tag read/write API such as Ndef. Instead, your NDEF message is delivered via NFC peer-to-peer. One way to do that is to use setNdefPushMessageCallback in your Activity's onCreate():

    NfcAdapter nfc = NfcAdapter.getDefaultAdapter(this);
    nfc.setNdefPushMessageCallback(new NfcAdapter.CreateNdefMessageCallback()
    {
        /*
         * (non-Javadoc)
         * @see android.nfc.NfcAdapter.CreateNdefMessageCallback#createNdefMessage(android.nfc.NfcEvent)
         */
        @Override
        public NdefMessage createNdefMessage(NfcEvent event) 
        {
            NdefRecord uriRecord = NdefRecord.createUri(Uri.encode("http://www.google.com/"));
            return new NdefMessage(new NdefRecord[] { uriRecord });
        }

    }, this, this);

The callback will be called when another NFC device comes near and a peer-to-peer connection is established. The callback then creates the NDEF message to be sent (in your case: the URL displayed in the webview).

edited Jan 09 '14 at 23:48

Jared Burrows

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answered Mar 20 '12 at 22:52

NFC guy

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Thank you, it works! I did find that the "connection" is kind of unstable between galaxy nexus 4.04 and galaxy S2 2.36. But in general, i was able to transfer the url. – DaiLak Mar 22 '12 at 19:28
You want to experiment somewhat with positioning the devices vertically relative to each other so the NFC antennas line up properly. – NFC guy Mar 22 '12 at 19:53
but how do you send multiple messages without disconnecting? – Pittfall Apr 24 '13 at 18:46
You can't :( That is a current limitation of the Android API, unfortunately. – NFC guy Apr 25 '13 at 10:16
@Pittfall you can only send one NdefMessage but it can contain multiple NDEF records. Maybe that helps... http://developer.android.com/reference/android/nfc/NdefMessage.html#NdefMessage(android.nfc.NdefRecord[]) – leo9r Sep 21 '13 at 10:03
setNdefPushMessageCallback is depracated – Dživo Jelić Jun 18 '22 at 10:48

Send a url between 2 NFC devices

1 Answers1