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已经阅读了许多与我类似的问题 - 如果我错过了解决问题的方法，我只能道歉，但我真的无法解决这个问题！

我设法让我的 nfc 活动正常工作 - 点击标签启动我的应用程序的正确活动 - 但未显示 ndef 消息，我不知道为什么......

该标签是一个 Mifare Ultralight，带有编码的纯文本消息。（模仿类型：纯/文本）

这是我的代码，谢谢大家的帮助，这个论坛应该有一个“捐赠啤酒”按钮！

package com.example.prototype02;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.PendingIntent;
import android.content.Intent;
import android.content.IntentFilter;
import android.nfc.NdefMessage;
import android.nfc.NfcAdapter;
import android.os.Bundle;
import android.os.Parcelable;
import android.widget.Toast;

public class nfcActivity extends Activity {
    private static final String TAG = "NFCReadTag";
    private NfcAdapter mNfcAdapter;
    private IntentFilter[] mNdefExchangeFilters;
    private PendingIntent mNfcPendingIntent;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.nfclayout);

        mNfcAdapter = NfcAdapter.getDefaultAdapter(this);

        mNfcPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,
                getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP
                | Intent.FLAG_ACTIVITY_CLEAR_TOP), 0);


        IntentFilter nfcIntent = new IntentFilter(NfcAdapter.ACTION_NDEF_DISCOVERED);
        nfcIntent.addDataScheme("text/plain");      
        mNdefExchangeFilters = new IntentFilter[] { nfcIntent };

    }

    @Override
    protected void onPause() {
        super.onPause();
        if(mNfcAdapter != null) mNfcAdapter.disableForegroundDispatch(this);
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);      
        if (mNfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())) {
            NdefMessage[] messages = null;
            Parcelable[] rawMsgs = intent.getParcelableArrayExtra(mNfcAdapter.EXTRA_NDEF_MESSAGES);
            if (rawMsgs != null) {
                messages = new NdefMessage[rawMsgs.length];
                for (int i = 0; i < rawMsgs.length; i++) {
                    messages[i] = (NdefMessage) rawMsgs[i];
                }}
                else if (rawMsgs == null){
                    Toast.makeText(getApplicationContext(), "No NDEF Message Read", Toast.LENGTH_LONG).show();
                }
            if(messages[0] != null) {
                String result="";
                byte[] payload = messages[0].getRecords()[0].getPayload();
                for (int b = 1; b<payload.length; b++) { // skip SOH
                    result += (char) payload[b];
                }
                Toast.makeText(getApplicationContext(), "Safe Location Registered - " + result, Toast.LENGTH_SHORT).show();
            }
        }
        else Toast.makeText(getApplicationContext(), "Intent Error...", Toast.LENGTH_LONG).show();

        }
    }
4

2 回答 2

1

如果您的 Activity 是由 NFC Intent 启动的，则onNewIntent()不会被调用（只有当 Activity 已经在前台时扫描标签时才会调用它）。尝试做一些类似调用onNewIntent(getIntent())的事情onCreate()。

于 2013-01-08T21:54:21.010 回答
0

尝试这样的事情：（取自 StickyNotes NFC 示例）

@Override
protected void onResume() {
    super.onResume();
    mResumed = true;
    // Sticky notes received from Android
    if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {
        NdefMessage[] messages = getNdefMessages(getIntent());
        byte[] payload = messages[0].getRecords()[0].getPayload();
        setNoteBody(new String(payload));
        setIntent(new Intent()); // Consume this intent.
    }
    enableNdefExchangeMode();
}

@Override
protected void onPause() {
    super.onPause();
    mResumed = false;
    mNfcAdapter.disableForegroundNdefPush(this);
}

@Override
protected void onNewIntent(Intent intent) {
    // NDEF exchange mode
    if (!mWriteMode && NfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())) {
        NdefMessage[] msgs = getNdefMessages(intent);
        promptForContent(msgs[0]);
    }

    // Tag writing mode
    if (mWriteMode && NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())) {
        Tag detectedTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
        writeTag(getNoteAsNdef(), detectedTag);
    }
}
于 2013-01-18T15:34:58.673 回答