NfcUtils.java

package be.digitalia.fosdem.utils;

import android.app.Activity;
import android.content.Intent;
import android.os.Build;

/**
 * NFC helper methods compatible with all API levels.
 * 
 * @author Christophe Beyls
 * 
 */
public class NfcUtils {

	/**
	 * Implement this interface to create application-specific data to be shared through Android Beam.
	 */
	public interface CreateNfcAppDataCallback {
		/**
		 * 
		 * @return The app data, or null if no data is currently available for sharing.
		 */
		byte[] createNfcAppData();
	}

	/**
	 * Call this method in an Activity, between onCreate() and onDestroy(), to make its content sharable using Android Beam if available. MIME type of the data
	 * to share will be "application/" followed by the app's package name. Declare it in your Manifest's intent filters as the data type with an action of
	 * android.nfc.action.NDEF_DISCOVERED to handle the NFC Intents on the receiver side.
	 * 
	 * @param activity
	 * @param callback
	 * @return true if NFC is available and the content was made available, false if not.
	 */
	public static boolean setAppDataPushMessageCallbackIfAvailable(Activity activity, final CreateNfcAppDataCallback callback) {
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
			return NfcSenderUtils.setAppDataPushMessageCallbackIfAvailable(activity, callback);
		}
		return false;
	}

	/**
	 * Determines if the intent contains NFC NDEF application-specific data to be extracted.
	 * 
	 * @param intent
	 * @return
	 */
	public static boolean hasAppData(Intent intent) {
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD_MR1) {
			return NfcReceiverUtils.hasAppData(intent);
		}
		return false;
	}

	/**
	 * Extracts application-specific data sent through NFC from an intent. You must first ensure that the intent contains NFC data by calling hasAppData().
	 * 
	 * @param intent
	 * @return The extracted data
	 */
	public static byte[] extractAppData(Intent intent) {
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD_MR1) {
			return NfcReceiverUtils.extractAppData(intent);
		}
		return null;
	}
}