我正在尝试使用以下示例将多个记录添加到一个NDefMessage但是当我尝试这样做时 - 我收到一条错误，指出“方法getBytes()未定义为输入TextView“
实施例： example
来源：
public class ViewCountry extends Activity implements CreateNdefMessageCallback,
OnNdefPushCompleteCallback {
NfcAdapter mNfcAdapter;
// TextView timeTv;
private static final int MESSAGE_SENT = 1;
private long rowID;
private TextView nameTv;
private TextView capTv;
private TextView codeTv;
private TextView timeTv;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.view_country);
setUpViews();
Bundle extras = getIntent().getExtras();
rowID = extras.getLong(CountryList.ROW_ID);
}
private void setUpViews() {
nameTv = (TextView) findViewById(R.id.nameText);
capTv = (TextView) findViewById(R.id.capText);
timeTv = (TextView) findViewById(R.id.timeEdit);
codeTv = (TextView) findViewById(R.id.codeText);
nameTv = (TextView) findViewById(R.id.nameText);
// Check for available NFC Adapter
mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
if (mNfcAdapter == null) {
nameTv = (TextView) findViewById(R.id.nameText);
nameTv.setText("NFC is not available on this device.");
timeTv = (TextView) findViewById(R.id.timeEdit);
timeTv.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);
}
}
@Override
public NdefMessage createNdefMessage(NfcEvent event) {
String message1 = nameTv.getText().toString();
String message2 = timeTv.getText().toString();
byte[] textBytes1 = nameTv.getBytes();
byte[] textBytes2 = timeTv.getBytes();
NdefRecord textRecord1 = new NdefRecord(NdefRecord.TNF_WELL_KNOWN,
message1.getBytes(), new byte[]{}, textBytes1);
NdefRecord textRecord2 = new NdefRecord(NdefRecord.TNF_WELL_KNOWN,
message2.getBytes(), new byte[]{}, textBytes2);
// String text = ("SSID");
NdefMessage msg = new NdefMessage(
new NdefRecord[]{
textRecord1,
textRecord2,
NdefRecord.createApplicationRecord("com.nfc.linked")
}
*/
//,NdefRecord.createApplicationRecord("com.nfc.linked")
);
return msg;
}
/**
* 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(), "Core Device Rules Sent!", Toast.LENGTH_LONG).show();
break;
}
}
};
@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];
// record 0 contains the MIME type, record 1 is the AAR, if present
nameTv.setText(new String(msg.getRecords()[0].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.options, 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);
}
}
@Override
protected void onResume()
{
super.onResume();
new LoadContacts().execute(rowID);
}
private class LoadContacts extends AsyncTask<Long, Object, Cursor>
{
DatabaseConnector dbConnector = new DatabaseConnector(ViewCountry.this);
@Override
protected Cursor doInBackground(Long... params)
{
dbConnector.open();
return dbConnector.getOneContact(params[0]);
}
@Override
protected void onPostExecute(Cursor result)
{
super.onPostExecute(result);
result.moveToFirst();
// get the column index for each data item
int nameIndex = result.getColumnIndex("name");
int capIndex = result.getColumnIndex("cap");
int codeIndex = result.getColumnIndex("code");
int timeIndex = result.getColumnIndex("time");
nameTv.setText(result.getString(nameIndex));
capTv.setText(result.getString(capIndex));
timeTv.setText(result.getString(timeIndex));
codeTv.setText(result.getString(codeIndex));
result.close();
dbConnector.close();
}
}
private void deleteContact()
{
AlertDialog.Builder alert = new AlertDialog.Builder(ViewCountry.this);
alert.setTitle(R.string.confirmTitle);
alert.setMessage(R.string.confirmMessage);
alert.setPositiveButton(R.string.delete_btn,
new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int button)
{
final DatabaseConnector dbConnector =
new DatabaseConnector(ViewCountry.this);
AsyncTask<Long, Object, Object> deleteTask =
new AsyncTask<Long, Object, Object>()
{
@Override
protected Object doInBackground(Long... params)
{
dbConnector.deleteContact(params[0]);
return null;
}
@Override
protected void onPostExecute(Object result)
{
finish();
}
};
deleteTask.execute(new Long[] { rowID });
}
}
);
alert.setNegativeButton(R.string.cancel_btn, null).show();
}
}
答案 0 :(得分：1)
对于TextView
类型，方法getBytes（）未定义
Simply TextView（作为对象）不提供getBytes()方法。但是如果你想将TextView的内容转换为bytes数组，你需要首先获取TextView的内容然后你可以使用getBytes（）
byte[] arr = nameTv.getText().toString().getBytes();
注意：如果要将整个对象转换为bytes数组，可以使用
示例：
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream writter = new ObjectOutputStream(baos);
writter.writeObject(<yourObject>);
byte[] arr = baos.toByteArray();
答案 1 :(得分：1)
那是因为TextView的对象没有getBytes()方法。
在您拥有nameTv.getBytes()的代码中，尝试将其替换为message1.getBytes()。看起来这就是你想要的。