我正在关注一个允许用户将数据保存到 NFC 标签的教程。我正在尝试修改教程源代码以包含第二个 EditText 字段并保存第二个标记，但是如果我注释掉以下行，我只能保存第二个 NDef 记录：
// write(message.getText().toString(),mytag);
我需要能够编写两个标签：
write(message.getText().toString(),mytag);
和
write(message.getText().toString(),mytag2);
...但我需要帮助将它们连接在一起。
这里有一个示例显示如何添加多个标签：
但我需要帮助格式化我当前的来源以反映这种方法。（每次我尝试时，我的日志中都会出现其他问题或强制关闭问题。）
提前致谢！
爪哇：
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.nfc.FormatException;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.Tag;
import android.nfc.tech.Ndef;
import android.nfc.tech.NdefFormatable;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
@SuppressLint({ "ParserError", "ParserError" })
public class MainActivity extends Activity{
NfcAdapter adapter;
PendingIntent pendingIntent;
IntentFilter writeTagFilters[];
boolean writeMode;
Tag mytag;
Tag mytag2;
Context ctx;
Context ctx2;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ctx=this;
Button btnWrite = (Button) findViewById(R.id.button);
final TextView message = (TextView)findViewById(R.id.edit_message);
ctx2=this;
final TextView message2 = (TextView)findViewById(R.id.edit_message2);
btnWrite.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v) {
try {
if(mytag==null){
Toast.makeText(ctx, ctx.getString(R.string.error_detected), Toast.LENGTH_LONG ).show();
if(mytag2==null){
Toast.makeText(ctx2, ctx2.getString(R.string.error_detected), Toast.LENGTH_LONG ).show();
}
}else{
// write(message.getText().toString(),mytag);
write(message.getText().toString(),mytag2);
Toast.makeText(ctx, ctx.getString(R.string.ok_writing), Toast.LENGTH_LONG ).show();
Toast.makeText(ctx2, ctx2.getString(R.string.ok_writing), Toast.LENGTH_LONG ).show();
}
} catch (IOException e) {
Toast.makeText(ctx, ctx.getString(R.string.error_writing), Toast.LENGTH_LONG ).show();
Toast.makeText(ctx2, ctx2.getString(R.string.error_writing), Toast.LENGTH_LONG ).show();
e.printStackTrace();
} catch (FormatException e) {
Toast.makeText(ctx, ctx.getString(R.string.error_writing) , Toast.LENGTH_LONG ).show();
Toast.makeText(ctx2, ctx2.getString(R.string.error_writing) , Toast.LENGTH_LONG ).show();
e.printStackTrace();
}
}
});
adapter = NfcAdapter.getDefaultAdapter(this);
pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
tagDetected.addCategory(Intent.CATEGORY_DEFAULT);
writeTagFilters = new IntentFilter[] { tagDetected };
}
private void write(String text, Tag tag) throws IOException, FormatException {
NdefRecord[] records = { createRecord(text) };
NdefMessage message = new NdefMessage(records);
// Get an instance of Ndef for the tag.
Ndef ndef = Ndef.get(tag);
// SUGGESTED IMPLEMENTATION
// mRecords = new NdefRecord[1 + records.length];
// mRecords[0] = record;
// System.arraycopy(records, 0, mRecords, 1, records.length);
// Enable I/O
ndef.connect();
// Write the message
ndef.writeNdefMessage(message);
// Close the connection
ndef.close();
}
private NdefRecord createRecord(String text) throws UnsupportedEncodingException {
String lang = "en";
byte[] textBytes = text.getBytes();
byte[] langBytes = lang.getBytes("US-ASCII");
int langLength = langBytes.length;
int textLength = textBytes.length;
byte[] payload = new byte[1 + langLength + textLength];
// set status byte (see NDEF spec for actual bits)
payload[0] = (byte) langLength;
// copy langbytes and textbytes into payload
System.arraycopy(langBytes, 0, payload, 1, langLength);
System.arraycopy(textBytes, 0, payload, 1 + langLength, textLength);
NdefRecord recordNFC = new NdefRecord(NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_TEXT, new byte[0], payload);
return recordNFC;
}
@Override
protected void onNewIntent(Intent intent){
if(NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())){
mytag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
mytag2 = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
Toast.makeText(this, this.getString(R.string.ok_detection) + mytag.toString(), Toast.LENGTH_LONG ).show();
}
}
@Override
public void onPause(){
super.onPause();
WriteModeOff();
}
@Override
public void onResume(){
super.onResume();
WriteModeOn();
}
private void WriteModeOn(){
writeMode = true;
adapter.enableForegroundDispatch(this, pendingIntent, writeTagFilters, null);
}
private void WriteModeOff(){
writeMode = false;
adapter.disableForegroundDispatch(this);
}
}
XML:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Please Enter Your Password: ">
</TextView>
<EditText
android:id="@+id/edit_message2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="2"
android:hint="SSID" />
<EditText
android:id="@+id/edit_message"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="2"
android:hint="WiFi Password" />
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Write!!" />
</LinearLayout>
教程源代码（显示上面只保存一个 NDef 记录的源代码的实现 - 我已经修改它以保存两个 NDef 记录）
http://www.framentos.com/en/android-tutorial/2012/07/31/write-hello-world-into-a-nfc-tag-with-a/