Android Nfc Beam数据传输
从NfcAdapter的官方文档我们可以得知，Android Beam技术可以实现简单的信息的传输，同样支持文件的传输。
简单消息的传输
一、简单信息的传输API：
1、enableForegroundNdefPush(Activity activity, NdefMessage message)
2、setNdefPushMessage (NdefMessage message, Activity activity, Activity... activities)
3、setNdefPushMessageCallback (NfcAdapter.CreateNdefMessageCallback callback, Activity activity, Activity... activities)
二、三者之间的区别：
1：方法一是API 10以后使用，方法二、三都是API 14以后才可以用；
2：方法二用于传输不可变的数据，而方法三多用于传输可变的数据；
三、应用：
方法一的应用
public class MainActivity extends AppCompatActivity{
private NfcAdapter nfcAdapter;
private PendingIntent pendingIntent;
private IntentFilter[] filters;
private String[][] techLists=null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
checkNdef();
}
private void checkNdef() {
nfcAdapter=NfcAdapter.getDefaultAdapter(this);
pendingIntent=PendingIntent.getActivity(MainActivity.this, 500, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
IntentFilter filter = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
try {
filter.addDataType("*/*");
filters=new IntentFilter[]{filter};
} catch (IntentFilter.MalformedMimeTypeException e) {
e.printStackTrace();
}
if (nfcAdapter==null){
Toast.makeText(this,"不支持NFC功能",Toast.LENGTH_SHORT).show();
}else{
if (nfcAdapter.isEnabled()){
Toast.makeText(this,"NFC功能已打开",Toast.LENGTH_SHORT).show();
}else{
Intent intent= new Intent(Settings.ACTION_NFC_SETTINGS);
startActivity(intent);
}
}
}
@Override
protected void onResume() {
super.onResume();
//前台调度系统
nfcAdapter.enableForegroundDispatch(MainActivity.this,pendingIntent,filters,techLists);
//enableForegroundNdefPush(Activity activity, NdefMessage message)的使用
NdefMessage ndefMessage=NfcWriteUtil.writeAbsoluteUri("http://www.baidu.com");
nfcAdapter.enableForegroundNdefPush(this,ndefMessage);
}
@Override
protected void onPause() {
super.onPause();
nfcAdapter.disableForegroundDispatch(MainActivity.this);
}
@Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
Tag tag=intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
}
}方法二的应用
//第一步，实现callBack
public class NfcP2pActivity extends AppCompatActivity implements NfcAdapter.CreateNdefMessageCallback{
private NfcAdapter nfcAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nfc_p2p);
checkNfcBeam();
//第二步，绑定callBack
nfcAdapter.setNdefPushMessageCallback(this,this);
}
private void checkNfcBeam() {
nfcAdapter = NfcAdapter.getDefaultAdapter(this);
if (nfcAdapter !=null){
if (!nfcAdapter.isEnabled()){
//支持NFC，但是没有打开
Intent intent = new Intent(Settings.ACTION_WIRELESS_SETTINGS);
startActivity(intent);
}else if(!nfcAdapter.isNdefPushEnabled()){
//API 16+
Intent intent = new Intent(Settings.ACTION_NFCSHARING_SETTINGS);
startActivity(intent);
}
}
}
@Override
public NdefMessage createNdefMessage(NfcEvent event) {
//封装数据，即写数据,发送数据
NdefMessage ndefMessage=NfcWriteUtil.writeText("我是测试", Locale.CANADA,true);
return ndefMessage;
}
@Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
//接收数据
setIntent(intent);
}
@Override
protected void onResume() {
super.onResume();
//判断数据是否为想要的
if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())){
//解析数据（读数据）
}
}
@Override
protected void onPause() {
super.onPause();
}
}
public class NfcP2p2Activity extends AppCompatActivity {
private NfcAdapter nfcAdapter;
private NdefMessage ndefMessage;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nfc_p2p);
checkNfcBeam();
nfcAdapter.setNdefPushMessage(ndefMessage,this);
}
private void checkNfcBeam() {
nfcAdapter = NfcAdapter.getDefaultAdapter(this);
if (nfcAdapter !=null){
if (!nfcAdapter.isEnabled()){
//支持NFC，但是没有打开
Intent intent = new Intent(Settings.ACTION_WIRELESS_SETTINGS);
startActivity(intent);
}else if(!nfcAdapter.isNdefPushEnabled()){
//API 16+
Intent intent = new Intent(Settings.ACTION_NFCSHARING_SETTINGS);
startActivity(intent);
}
}
}
@Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
//接收数据
setIntent(intent);
}
@Override
protected void onResume() {
super.onResume();
//判断数据是否为想要的
if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())){
//解析数据（读数据）
}
}
@Override
protected void onPause() {
super.onPause();
}
}一、API：
1、setBeamPushUris(Uri[] uris, Activity activity)
2、setBeamPushUrisCallback(NfcAdapter.CreateBeamUrisCallback callback, Activity activity)
二、应用：
public class NFCFileActivity extends Activity implements CreateBeamUrisCallback {
private NfcAdapter mNfcAdapter;
private PendingIntent mPendingIntent;
private final String targetFilename = "/sdcard/temp_icon.png";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_nfcfile);
mNfcAdapter = mNfcAdapter.getDefaultAdapter(this);
mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,
getClass()), 0);
try {
InputStream is = getResources().getAssets().open("icon.png");
FileOutputStream fos = new FileOutputStream(targetFilename);
byte[] buffer = new byte[10000];
int n = is.read(buffer);
fos.write(buffer, 0, n);
fos.close();
is.close();
} catch (Exception e) {
}
mNfcAdapter.setBeamPushUrisCallback(this, this);
}
@Override
public Uri[] createBeamUris(NfcEvent event) {
Uri[] uris = new Uri[1];
Uri uri = Uri.parse("file://" + targetFilename);
uris[0] = uri;
return uris;
}
}