Android Open Source - MyNFCWriter Nfc Writer

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License

The source code is released under:

Apache License

Java Source Code

/**
 * /* w w  w . ja  v a2  s. c om*/
 */
package jp.co.iti.mynfcwriter;

import java.io.IOException;
import java.nio.charset.Charset;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.nfc.FormatException;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.Tag;
import android.nfc.TagLostException;
import android.nfc.tech.Ndef;

/**
 * @author jumpei
 *
 */
public class NfcWriter {

  private NfcAdapter nfcAdapter = null;
  private String errorMessage = null;

  public NfcWriter(Context context) {
    // Get default NFC adapter
    this.nfcAdapter = NfcAdapter.getDefaultAdapter(context);
  }

  public void enable(Activity activity, PendingIntent pendingIntent) {
    this.nfcAdapter.enableForegroundDispatch(activity, pendingIntent, null, null);
  }

  public void disable(Activity activity) {
    this.nfcAdapter.disableForegroundDispatch(activity);
  }

  public boolean write(Context context, Intent intent, String targetUrl) {
    boolean result = false;

    this.errorMessage = null;

    Tag tag = (Tag)intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
    if (tag == null) {
      this.errorMessage = "Failed: Tag is null.";
      return result;
    }

    Ndef ndef = Ndef.get(tag);
    if (ndef == null) {
      this.errorMessage = "Failed: Wrong tag format.";
      return result;
    }

    NdefMessage ndefMessage = this.createMessage(targetUrl);
    if (ndefMessage == null) {
      this.errorMessage = "Failed: NdefMessage is null.";
      return result;
    }

    if (this.writeMessage(ndef, ndefMessage)) {
      result = true;
    }

    return result;
  }

  public String getErrorMessage() {
    return this.errorMessage;
  }


    private NdefMessage createMessage(String targetUrl) {
        NdefRecord[] rs = new NdefRecord[] {
          createUriRecord(targetUrl),
            createActionRecord() 
        };
        NdefMessage spPayload = new NdefMessage(rs);

        NdefRecord spRecord = new NdefRecord(NdefRecord.TNF_WELL_KNOWN,
                          NdefRecord.RTD_SMART_POSTER,
                          new byte[0],
                          spPayload.toByteArray());
        return new NdefMessage(new NdefRecord[]{spRecord});
    }

    private NdefRecord createUriRecord(String url) {
        return NdefRecord.createUri(url);
    }

    private NdefRecord createActionRecord() {
        byte[] typeField = "act".getBytes(Charset.forName("US-ASCII"));
        byte[] payload = {(byte) 0x00};
        return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, 
                              typeField,
                              new byte[0],
                              payload); // ?y2?z
    }

    private boolean writeMessage(Ndef ndef, NdefMessage ndefMessage) {
      boolean result = false;
   
        if (!ndef.isWritable()) {
          this.errorMessage = "Failed: Readonly.";
            return result;
        }

        int messageSize = ndefMessage.toByteArray().length;
        if (messageSize > ndef.getMaxSize()) {
          this.errorMessage = "Failed: Overflow.";
            return false;

        }

        try {
            if (!ndef.isConnected()) {
              ndef.connect();
            }
            ndef.writeNdefMessage(ndefMessage);
            result = true;

        } catch (TagLostException e) {
          this.errorMessage = "Failed: " + e.getLocalizedMessage();

        } catch (IOException e) {
          this.errorMessage = "Failed: " + e.getLocalizedMessage();

        } catch (FormatException e) {
          this.errorMessage = "Failed: " + e.getLocalizedMessage();

        } finally {
            try {
                ndef.close();
            } catch (IOException e) {
                // ignore.
            }
        }

        return result;
    }
}

Java Source Code List

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