AndroidBeam_S

import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.nfc.NfcAdapter;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import it.stesp.news.R;

public class NFC extends Activity {

    public static final String TAG_LOG = NFC.class.getName();

    NfcAdapter mNfcAdapter;
    boolean mAndroidBeamAvailable = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.nfc_);

        if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_NFC)) { // NFC isn't available on the device
            Log.i(TAG_LOG, "No NFC");
        } else if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN_MR1) { // Android Beam file transfer isn't supported
            Log.i(TAG_LOG, "No Android Beam");
            mAndroidBeamAvailable = false;
        } else { // Android Beam file transfer is available, continue
            mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
            mAndroidBeamAvailable = true;
        }

        Button btn_nfc = (Button) findViewById(R.id.btn_nfc);
        btn_nfc.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                sendFile();
            }
        });
    }

    private void sendFile() {
        if (mAndroidBeamAvailable) {
            // Check whether NFC is enabled on device
            if (!mNfcAdapter.isEnabled()) {
                // NFC is disabled, show the settings UI
                // to enable NFC
                Toast.makeText(this, "Please enable NFC.",
                        Toast.LENGTH_SHORT).show();
                startActivity(new Intent(Settings.ACTION_NFC_SETTINGS));
            }
            // Check whether Android Beam feature is enabled on device
            else if (!mNfcAdapter.isNdefPushEnabled()) {
                // Android Beam is disabled, show the settings UI
                // to enable Android Beam
                Toast.makeText(this, "Please enable Android Beam.",
                        Toast.LENGTH_SHORT).show();
                startActivity(new Intent(Settings.ACTION_NFCSHARING_SETTINGS));
            } else {
                // NFC and Android Beam both are enabled
                File fileToTransfer = getDummyFile();

                mNfcAdapter.setBeamPushUris(
                        new Uri[]{Uri.fromFile(fileToTransfer)}, this);
                Log.i(TAG_LOG, "Uri push");
            }
        }
    }

    private File getDummyFile() {
        File dir = getExternalFilesDir(null);
        if (!dir.exists()) dir.mkdirs();

        String filename = "dummy.txt";
        File file = new File(dir, filename);

        try {
            String text = "prova";

            FileOutputStream out = new FileOutputStream(file);
            out.write(text.getBytes());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return file;
    }
}