Question

After installing Android 2.3.4 on my Nexus S, NFC Apps doesn´t start anymore.

I’ve tried with the three intents (NDEF_DISCOVERED,TECH_DISCOVERED,TAG_DISCOVERED) described in google documentation, but any of them solves the problem, Nexux S keeps on opening default google applications and ignore my app.

I had this in the manifest

<intent-filter>
<action android:name="android.nfc.action.TAG_DISCOVERED"/>
</intent-filter>

and if I am not wrong it seems to be supported in news 2.3.3, why the Nexus S ignore it?

Could you help me please.

Best Regards,
Hugo.

Answer 1

You need to add this to your intent filters:

<intent-filter>
   <action android:name="android.nfc.action.NDEF_DISCOVERED"/>
</intent-filter>

When a tag is scanned, Android should show a popup asking which app to handle it.

Update

Based on additional info from your comment, the problem is that your tag contains information which is recognized by Android. In this case, that is a URL. Since Android can find an app (the default NFC app) which can handle urls, then that app will take priority and be called instead of an app which simple handles tag discovery. Tag discovery is only dispatched if no other intent filter matched the tag. To quote the docs:

android.nfc.action.TAG_DISCOVERED:
This intent starts if no Activities
handle the NDEF_DISCOVERED and
TECH_DISCOVERED intents or if the tag
that is scanned is unknown.

So you must declare your tag to handle messages in the tags as well. You need to specify exactly the type of data you are targeting as well (in this case, urls), else the Google Android app will still take precedence for URLs. You can read more information on the Android NFC page