android NFC读取源码

/* * Copyright (C) 2010 The Android Open Source Project * Copyright (C) 2011 Adam Nybäck * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package se.anyro.nfc_reader; import java.nio.charset.Charset; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import java.util.List; import java.util.Locale; import se.anyro.nfc_reader.record.ParsedNdefRecord; import android.app.Activity; import android.app.AlertDialog; import android.app.PendingIntent; import android.content.DialogInterface; import android.content.Intent; import android.nfc.NdefMessage; import android.nfc.NdefRecord; import android.nfc.NfcAdapter; import android.nfc.Tag; import android.nfc.tech.MifareClassic; import android.nfc.tech.MifareUltralight; import android.os.Bundle; import android.os.Parcelable; import android.provider.Settings; import android.view.LayoutInflater; import android.widget.LinearLayout; import android.widget.TextView; /** * An {@link Activity} which handles a broadcast of a new tag that the device just discovered. */ public class TagViewer extends Activity { private static final DateFormat TIME_FORMAT = SimpleDateFormat.getDateTimeInstance(); private LinearLayout mTagContent; private NfcAdapter mAdapter; private PendingIntent mPendingIntent; private NdefMessage mNdefPushMessage; private AlertDialog mDialog; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.tag_viewer); mTagContent = (LinearLayout) findViewById(R.id.list); resolveIntent(getIntent()); mDialog = new AlertDialog.Builder(this).setNeutralButton("Ok", null).create(); mAdapter = NfcAdapter.getDefaultAdapter(this); if (mAdapter == null) { showMessage(R.string.error, R.string.no_nfc); finish(); return; } mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0); mNdefPushMessage = new NdefMessage(new NdefRecord[] { newTextRecord( "Message from NFC Reader :-)", Locale.ENGLISH, true) }); } private void showMessage(int title, int message) { mDialog.setTitle(title); mDialog.setMessage(getText(message)); mDialog.show(); } private NdefRecord newTextRecord(String text, Locale locale, boolean encodeInUtf8) { byte[] langBytes = locale.getLanguage().getBytes(Charset.forName("US-ASCII")); Charset utfEncoding = encodeInUtf8 ? Charset.forName("UTF-8") : Charset.forName("UTF-16"); byte[] textBytes = text.getBytes(utfEncoding); int utfBit = encodeInUtf8 ? 0 : (1 << 7); char status = (char) (utfBit + langBytes.length); byte[] data = new byte[1 + langBytes.length + textBytes.length]; data[0] = (byte) status; System.arraycopy(langBytes, 0, data, 1, langBytes.length); System.arraycopy(textBytes, 0, data, 1 + langBytes.length, textBytes.length); return new NdefRecord(NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_TEXT, new byte[0], data); } @Override protected void onResume() { super.onResume(); if (mAdapter != null) { if (!mAdapter.isEnabled()) { showWirelessSettingsDialog(); } mAdapter.enableForegroundDispatch(this, mPendingIntent, null, null); mAdapter.enableForegroundNdefPush(this, mNdefPushMessage); } } @Override protected void onPause() { super.onPause(); if (mAdapter != null) { mAdapter.disableForegroundDispatch(this); mAdapter.disableForegroundNdefPush(this); } } private void showWirelessSettingsDialog() { AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setMessage(R.string.nfc_disabled); builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialogInterface, int i) { Intent intent = new Intent(Settings.ACTION_WIRELESS_SETTINGS); startActivity(intent); } }); builder.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialogInterface, int i) { finish(); } }); builder.create().show(); return; } private void resolveIntent(Intent intent) { String action = intent.getAction(); if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(action) || NfcAdapter.ACTION_TECH_DISCOVERED.equals(action) || NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) { Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES); NdefMessage[] msgs; if (rawMsgs != null) { msgs = new NdefMessage[rawMsgs.length]; for (int i = 0; i < rawMsgs.length; i++) { msgs[i] = (NdefMessage) rawMsgs[i]; } } else { // Unknown tag type byte[] empty = new byte[0]; byte[] id = intent.getByteArrayExtra(NfcAdapter.EXTRA_ID); Parcelable tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG); byte[] payload = dumpTagData(tag).getBytes(); NdefRecord record = new NdefRecord(NdefRecord.TNF_UNKNOWN, empty, id, payload); NdefMessage msg = new NdefMessage(new NdefRecord[] { record }); msgs = new NdefMessage[] { msg }; } // Setup the views buildTagViews(msgs); } } private String dumpTagData(Parcelable p) { StringBuilder sb = new StringBuilder(); Tag tag = (Tag) p; byte[] id = tag.getId(); sb.append("Tag ID (hex): ").append(getHex(id)).append("\n"); sb.append("Tag ID (dec): ").append(getDec(id)).append("\n"); sb.append("ID (reversed): ").append(getReversed(id)).append("\n"); String prefix = "android.nfc.tech."; sb.append("Technologies: "); for (String tech : tag.getTechList()) { sb.append(tech.substring(prefix.length())); sb.append(", "); } sb.delete(sb.length() - 2, sb.length()); for (String tech : tag.getTechList()) { if (tech.equals(MifareClassic.class.getName())) { sb.append('\n'); MifareClassic mifareTag = MifareClassic.get(tag); String type = "Unknown"; switch (mifareTag.getType()) { case MifareClassic.TYPE_CLASSIC: type = "Classic"; break; case MifareClassic.TYPE_PLUS: type = "Plus"; break; case MifareClassic.TYPE_PRO: type = "Pro"; break; } sb.append("Mifare Classic type: "); sb.append(type); sb.append('\n'); sb.append("Mifare size: "); sb.append(mifareTag.getSize() + " bytes"); sb.append('\n'); sb.append("Mifare sectors: "); sb.append(mifareTag.getSecto