我正在尝试重建我的 NFC 标签阅读器
我收到以下错误:
java.lang.ArrayIndexOutOfBoundsException: length=1; index=1
在线上:
NdefMessage msg2 = (NdefMessage) rawMsgs[1];
我了解该问题通常与尝试访问不存在的数组项有关,但是我真的不确定如何在以下实现中解决该问题。
附言
该问题仅在扫描新的 NFC 标签时出现。我注意到一些非常有趣的东西......
如果我注释掉以下两行,应用程序不会崩溃并成功扫描标签!
// NdefMessage msg2 = (NdefMessage) rawMsgs[1];
// beamMsg2.setText(new String(msg.getRecords()[1].getPayload()));
资源:
public class Nfc extends Activity implements CreateNdefMessageCallback,
OnNdefPushCompleteCallback {
NfcAdapter mNfcAdapter;
TextView beamMsg;
TextView beamMsg2;
private static final int MESSAGE_SENT = 1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.nfc);
beamMsg = (TextView) findViewById(R.id.msg);
beamMsg2 = (TextView) findViewById(R.id.msg_ID);
beamMsg.setText("Peter Smith");
beamMsg2.setText("123456");
// Check for available NFC Adapter
mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
if (mNfcAdapter == null) {
beamMsg = (TextView) findViewById(R.id.msg);
beamMsg2= (TextView) findViewById(R.id.msg_ID);
beamMsg.setText("NFC is not available on this device.");
beamMsg2.setText("NFC is not available on this device.");
} else {
// Register callback to set NDEF message
mNfcAdapter.setNdefPushMessageCallback(this, this);
// Register callback to listen for message-sent success
mNfcAdapter.setOnNdefPushCompleteCallback(this, this);
}
}
public void submitClicked(View v)
{
Toast toast = Toast.makeText(getApplicationContext(), R.string.info,
Toast.LENGTH_LONG);
toast.show();
}
/**
* Implementation for the CreateNdefMessageCallback interface
*/
@Override
public NdefMessage createNdefMessage(NfcEvent event) {
NdefMessage msg = new NdefMessage(NdefRecord.createMime(
beamMsg.getText() .toString(), null));
return msg;
}
public NdefMessage createNdefMessage_two(NfcEvent event) {
NdefMessage msg2 = new NdefMessage(NdefRecord.createMime(
beamMsg2.getText() .toString(), null));
return msg2;
}
/**
* Implementation for the OnNdefPushCompleteCallback interface
*/
@Override
public void onNdefPushComplete(NfcEvent arg0) {
// A handler is needed to send messages to the activity when this
// callback occurs, because it happens from a binder thread
mHandler.obtainMessage(MESSAGE_SENT).sendToTarget();
}
/** This handler receives a message from onNdefPushComplete */
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_SENT:
Toast.makeText(getApplicationContext(), "Message sent!", Toast.LENGTH_LONG).show();
break;
}
}
};
@Override
public void onResume() {
super.onResume();
// Check to see that the Activity started due to an Android Beam
if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {
processIntent(getIntent());
}
}
@Override
public void onNewIntent(Intent intent) {
// onResume gets called after this to handle the intent
setIntent(intent);
}
/**
* Parses the NDEF Message from the intent and prints to the TextView
*/
void processIntent(Intent intent) {
Parcelable[] rawMsgs = intent.getParcelableArrayExtra(
NfcAdapter.EXTRA_NDEF_MESSAGES);
// only one message sent during the beam
NdefMessage msg = (NdefMessage) rawMsgs[0];
NdefMessage msg2 = (NdefMessage) rawMsgs[1];
// record 0 contains the MIME type, record 1 is the AAR, if present
beamMsg.setText(new String(msg.getRecords()[0].getPayload()));
beamMsg2.setText(new String(msg.getRecords()[1].getPayload()));
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// If NFC is not available, we won't be needing this menu
if (mNfcAdapter == null) {
return super.onCreateOptionsMenu(menu);
}
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return true;
}
// @Override
// public boolean onOptionsItemSelected(MenuItem item) {
// switch (item.getItemId()) {
// case R.id.menu_settings:
// Intent intent = new Intent(Settings.ACTION_NFCSHARING_SETTINGS);
// startActivity(intent);
// return true;
// default:
// return super.onOptionsItemSelected(item);
// }
}
//}//}
回答后编辑:
public class Connect extends Activity implements CreateNdefMessageCallback,
OnNdefPushCompleteCallback {
NfcAdapter mNfcAdapter;
TextView beamMsg;
TextView beamMsg2;
private static final int MESSAGE_SENT = 1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.connect);
beamMsg = (TextView) findViewById(R.id.msg);
beamMsg2 = (TextView) findViewById(R.id.msg_ID);
beamMsg.setText("Peter Smith");
beamMsg2.setText("123456");
// Check for available NFC Adapter
mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
if (mNfcAdapter == null) {
beamMsg = (TextView) findViewById(R.id.msg);
beamMsg2= (TextView) findViewById(R.id.msg_ID);
beamMsg.setText("NFC is not available on this device.");
beamMsg2.setText("NFC is not available on this device.");
} else {
// Register callback to set NDEF message
mNfcAdapter.setNdefPushMessageCallback(this, this);
// Register callback to listen for message-sent success
mNfcAdapter.setOnNdefPushCompleteCallback(this, this);
}
}
public void submitClicked(View v)
{
Toast toast = Toast.makeText(getApplicationContext(), R.string.info,
Toast.LENGTH_LONG);
toast.show();
}
/**
* Implementation for the CreateNdefMessageCallback interface
*/
@Override
public NdefMessage createNdefMessage(NfcEvent event) {
NdefMessage msg = new NdefMessage(NdefRecord.createMime(
beamMsg.getText() .toString(), null));
return msg;
}
public NdefMessage createNdefMessage_two(NfcEvent event) {
NdefMessage msg2 = new NdefMessage(NdefRecord.createMime(
beamMsg2.getText() .toString(), null));
return msg2;
}
/**
* Implementation for the OnNdefPushCompleteCallback interface
*/
@Override
public void onNdefPushComplete(NfcEvent arg0) {
// A handler is needed to send messages to the activity when this
// callback occurs, because it happens from a binder thread
mHandler.obtainMessage(MESSAGE_SENT).sendToTarget();
}
/** This handler receives a message from onNdefPushComplete */
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_SENT:
Toast.makeText(getApplicationContext(), "Message sent!", Toast.LENGTH_LONG).show();
break;
}
}
};
@Override
public void onResume() {
super.onResume();
// Check to see that the Activity started due to an Android Beam
if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {
processIntent(getIntent());
}
}
@Override
public void onNewIntent(Intent intent) {
// onResume gets called after this to handle the intent
setIntent(intent);
}
/**
* Parses the NDEF Message from the intent and prints to the TextView
*/
void processIntent(Intent intent) {
Parcelable[] rawMsgs = intent.getParcelableArrayExtra(
NfcAdapter.EXTRA_NDEF_MESSAGES);
// only one message sent during the beam
NdefMessage[] msg = new NdefMessage[rawMsgs.length];
for (int i = 0; i < msg.length; i++) {
msg[i] = (NdefMessage) rawMsgs[i];
// record 0 contains the MIME type, record 1 is the AAR, if present
beamMsg[i].setText(new String(msg[i].getRecords()[1].getPayload()));
beamMsg2[i].setText(new String(msg[i].getRecords()[1].getPayload()));
}}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// If NFC is not available, we won't be needing this menu
if (mNfcAdapter == null) {
return super.onCreateOptionsMenu(menu);
}
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return true;
}
// @Override
// public boolean onOptionsItemSelected(MenuItem item) {
// switch (item.getItemId()) {
// case R.id.menu_settings:
// Intent intent = new Intent(Settings.ACTION_NFCSHARING_SETTINGS);
// startActivity(intent);
// return true;
// default:
// return super.onOptionsItemSelected(item);
// }
}
//}//}