Android Beam - 如何傳輸正確的數據？

Question

我現在正在進行一個android梁項目。 我從Android開發人員那里復制了一個測試類。

我的問題是發送正確的數據。 如果我將（p2p）與另一台設備連接並按“Tab to beam”，則只有到Android市場的URI到達。 但是，如果我打開瀏覽器，連接並選項卡，瀏覽器中的當前URL將會到達。

如何告訴android應該發送哪個視圖或文本？ 我沒弄明白。 我只想發一個簡單的字符串“你好！” 例如

這是代碼：

package peer.to.peer;

import java.nio.charset.Charset;
import android.app.Activity;
import android.nfc.NdefMessage;
import android.nfc.NdefRecord;
import android.nfc.NfcAdapter;
import android.nfc.NfcAdapter.CreateNdefMessageCallback;
import android.nfc.NfcAdapter.OnNdefPushCompleteCallback;
import android.nfc.NfcEvent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;


public class Peer2peerActivity extends Activity implements     
CreateNdefMessageCallback,     OnNdefPushCompleteCallback {
   private Button sendButton;
   private EditText textfield;
   NfcAdapter mNfcAdapter;
   private static final int MESSAGE_SENT = 1;


   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.main);

          //initialisierung
          sendButton=(Button) findViewById(R.id.button);
          textfield= (EditText) findViewById(R.id.textfield);

          //mNfcAdapter = NfcAdapter.getDefaultAdapter(this);

          //if(mNfcAdapter==null) toast("NFC ist nicht vorhanden");
          //else toast("NFC ist  vorhandne");


          toast("start");

          sendButton.setOnClickListener(mTagWriter);
   }

   //lokaler OnClickListener für den Button
   private View.OnClickListener mTagWriter = new View.OnClickListener() {
    public void onClick(View arg0) {
        // Write to a tag for as long as the dialog is shown.
        //disableNdefExchangeMode();
        //enableTagWriteMode();

          toast(textfield.getText().toString());
    }
   };
   //notification-methode
   public void toast(String text){
          Toast.makeText(this, text, Toast.LENGTH_SHORT).show();
   }

   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();         
   }

   public NdefMessage createNdefMessage(NfcEvent event) {
    String text = (textfield.toString());
    NdefRecord uriRecord = new NdefRecord(
              NdefRecord.TNF_ABSOLUTE_URI ,
              "http://www.google.de".getBytes(Charset.forName("US-ASCII")),
              new byte[0], new byte[0]);
    NdefMessage msg = new NdefMessage(
            new NdefRecord[] { uriRecord
    //createMimeRecord("text/plain", text.getBytes())
     /**
      * The Android Application Record (AAR) is commented out. When a device
      * receives a push with an AAR in it, the application specified in the AAR
      * is guaranteed to run. The AAR overrides the tag dispatch system.
      * You can add it back in to guarantee that this
      * activity starts when receiving a beamed message. For now, this code
      * uses the tag dispatch system.
      */
      //,NdefRecord.createApplicationRecord("com.example.android.beam")
    });
    return msg;

   }

   /**
 * Creates a custom MIME type encapsulated in an NDEF record
 *
 * @param mimeType
 */
public NdefRecord createMimeRecord(String mimeType, byte[] payload) {
    byte[] mimeBytes = mimeType.getBytes(Charset.forName("US-ASCII"));
    NdefRecord mimeRecord = new NdefRecord(
            NdefRecord.TNF_MIME_MEDIA, mimeBytes, new byte[0], payload);
    return mimeRecord;
}

/** 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;
        }
    }
};
}

提前致謝

漿果

Answer 1

您正在獲取URI，因為第一條記錄是指向google.de的URI記錄。 將uriRecord替換為對createMimeRecord（）的調用，您應該獲得將mime類型設置為text / plain的文本。

Answer 2

您需要更改createNdefMessage以發送簡單消息。

String text = (textfield.toString());
NdefMessage msg = new NdefMessage(NdefRecord.createMime( "application/com.example.android.beam", text.getBytes()));
return msg;