NFC读写实例

2022-11-14 15:01:24

package com.sy.nfc.test;

import java.io.IOException;

import android.nfc.NdefMessage;

import android.nfc.NdefRecord;

import android.nfc.NfcAdapter;

import android.nfc.Tag;

import android.nfc.tech.MifareClassic;

import android.nfc.tech.Ndef;

import android.nfc.tech.NdefFormatable;

import android.nfc.tech.NfcA;

import android.os.Bundle;

import android.os.Parcelable;

import android.annotation.SuppressLint;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.PendingIntent;

import android.content.DialogInterface;

import android.content.Intent;

import android.content.IntentFilter;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.TextView;

import android.widget.Toast;

/**

 *

 * @author shenyang

 * @see

 * @des

 *

 *      Nfc 标签的扫描

 *

 *

 */

@SuppressLint("NewApi")

public class ReadTag extends Activity {

    private NfcAdapter nfcAdapter;

    private TextView resultText;

    private PendingIntent pendingIntent;

    private IntentFilter[] mFilters;

    private String[][] mTechLists;

    private Button mJumpTagBtn;

    private boolean isFirst = true;

    @SuppressLint("NewApi")

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        // 获取nfc适配器，判断设备是否支持NFC功能

        nfcAdapter = NfcAdapter.getDefaultAdapter(this);

        if (nfcAdapter == null) {

            Toast.makeText(this, getResources().getString(R.string.no_nfc),

                    Toast.LENGTH_SHORT).show();

            finish();

            return;

        } else if (!nfcAdapter.isEnabled()) {

            Toast.makeText(this, getResources().getString(R.string.open_nfc),

                    Toast.LENGTH_SHORT).show();

            finish();

            return;

        }

        setContentView(R.layout.read_tag);

        // 显示结果Text

        resultText = (TextView) findViewById(R.id.resultText);

        // 写入标签按钮

        mJumpTagBtn = (Button) findViewById(R.id.jump);

        mJumpTagBtn.setOnClickListener(new WriteBtnOnClick());

        pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,

                getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

        IntentFilter ndef = new IntentFilter(NfcAdapter.ACTION_TECH_DISCOVERED);

        ndef.addCategory("*/*");

        mFilters = new IntentFilter[] { ndef };// 过滤器

        mTechLists = new String[][] {

                new String[] { MifareClassic.class.getName() },

                new String[] { NfcA.class.getName() } };// 允许扫描的标签类型

    }

    @SuppressLint("NewApi")

    @Override

    protected void onResume() {

        // TODO Auto-generated method stub

        super.onResume();

        nfcAdapter.enableForegroundDispatch(this, pendingIntent, mFilters,

                mTechLists);

        if (isFirst) {

            if (NfcAdapter.ACTION_TECH_DISCOVERED.equals(getIntent().getAction())) {

                String result = processIntent(getIntent());

                resultText.setText(result);

            }

            isFirst = false;

        }

    }

    @Override

    protected void onNewIntent(Intent intent) {

        // TODO Auto-generated method stub

        super.onNewIntent(intent);

        if (NfcAdapter.ACTION_TECH_DISCOVERED.equals(intent.getAction())) {

            String result = processIntent(intent);

            resultText.setText(result);

        }

    }

    /**

     * 获取tab标签中的内容

     *

     * @param intent

     * @return

     */

    @SuppressLint("NewApi")

    private String processIntent(Intent intent) {

        Parcelable[] rawmsgs = intent

                .getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);

        NdefMessage msg = (NdefMessage) rawmsgs[0];

        NdefRecord[] records = msg.getRecords();

        String resultStr = new String(records[0].getPayload());

        return resultStr;

    }

    /**

     * 按钮点击事件

     *

     * @author shenyang

     *

     */

    class WriteBtnOnClick implements OnClickListener {

        @Override

        public void onClick(View v) {

            // TODO Auto-generated method stub

            switch (v.getId()) {

            case R.id.jump:

                Intent intent = new Intent(ReadTag.this, WriteTag.class);

                startActivity(intent);

            default:

                break;

            }

        }

    }

}

读标签内容代码展开

package com.sy.nfc.test;

import java.io.IOException;

import android.annotation.SuppressLint;

import android.app.Activity;

import android.app.AlertDialog;

import android.app.PendingIntent;

import android.content.DialogInterface;

import android.content.Intent;

import android.content.IntentFilter;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.nfc.NdefMessage;

import android.nfc.NdefRecord;

import android.nfc.NfcAdapter;

import android.nfc.Tag;

import android.nfc.tech.MifareClassic;

import android.nfc.tech.Ndef;

import android.nfc.tech.NdefFormatable;

import android.nfc.tech.NfcA;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

/**

 * 写入标签

 *

 * @warn：弹出dialog 允许写入

 * @author shenyang

 *

 */

@SuppressLint("NewApi")

public class WriteTag extends Activity {

    private IntentFilter[] mWriteTagFilters;

    private NfcAdapter nfcAdapter;

    PendingIntent pendingIntent;

    String[][] mTechLists;

    Button writeBtn;

    boolean isWrite = false;

    EditText mContentEditText;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        // TODO Auto-generated method stub

        super.onCreate(savedInstanceState);

        setContentView(R.layout.write_tag);

        writeBtn = (Button) findViewById(R.id.writeBtn);

        writeBtn.setOnClickListener(new WriteOnClick());

        mContentEditText = (EditText) findViewById(R.id.content_edit);

        // 获取nfc适配器，判断设备是否支持NFC功能

        nfcAdapter = NfcAdapter.getDefaultAdapter(this);

        if (nfcAdapter == null) {

            Toast.makeText(this, getResources().getString(R.string.no_nfc),

                    Toast.LENGTH_SHORT).show();

            finish();

            return;

        } else if (!nfcAdapter.isEnabled()) {

            Toast.makeText(this, getResources().getString(R.string.open_nfc),

                    Toast.LENGTH_SHORT).show();

            finish();

            return;

        }

        pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,

                getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);

        // 写入标签权限

        IntentFilter writeFilter = new IntentFilter(

                NfcAdapter.ACTION_TECH_DISCOVERED);

        mWriteTagFilters = new IntentFilter[] { writeFilter };

        mTechLists = new String[][] {

                new String[] { MifareClassic.class.getName() },

                new String[] { NfcA.class.getName() } };// 允许扫描的标签类型

    }

    /**

     * 写入标签按钮点击事件监听

     *

     * @author shenyang

     *

     */

    class WriteOnClick implements OnClickListener {

        @Override

        public void onClick(View v) {

            // TODO Auto-generated method stub

            isWrite = true;

            AlertDialog.Builder builder = new AlertDialog.Builder(WriteTag.this)

                    .setTitle("请将标签靠近！");

            builder.setNegativeButton("确定",

                    new DialogInterface.OnClickListener() {

                        @Override

                        public void onClick(DialogInterface dialog, int which) {

                            // TODO Auto-generated method stub

                            dialog.dismiss();

                            mContentEditText.setText("");

                            isWrite = false;

                            WriteTag.this.finish();

                        }

                    });

            builder.setPositiveButton("取消",

                    new DialogInterface.OnClickListener() {

                        @Override

                        public void onClick(DialogInterface dialog, int which) {

                            // TODO Auto-generated method stub

                            dialog.dismiss();

                            isWrite = false;

                        }

                    });

            builder.create();

            builder.show();

        }

    }

    @Override

    protected void onResume() {

        // TODO Auto-generated method stub

        super.onResume();

        nfcAdapter.enableForegroundDispatch(this, pendingIntent,

                mWriteTagFilters, mTechLists);

    }

    // 写入模式时，才执行写入操作

    @Override

    protected void onNewIntent(Intent intent) {

        // TODO Auto-generated method stub

        super.onNewIntent(intent);

        if (isWrite == true

                && NfcAdapter.ACTION_TECH_DISCOVERED.equals(intent.getAction())) {

            Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);

            NdefMessage ndefMessage = getNoteAsNdef();

            if (ndefMessage != null) {

                writeTag(getNoteAsNdef(), tag);

            } else {

                showToast("请输入您要写入标签的内容");

            }

        }

    }

    // 根据文本生成一个NdefRecord

    private NdefMessage getNoteAsNdef() {

        String text = mContentEditText.getText().toString();

        if (text.equals("")) {

            return null;

        } else {

            byte[] textBytes = text.getBytes();

            // image/jpeg text/plain

            NdefRecord textRecord = new NdefRecord(NdefRecord.TNF_MIME_MEDIA,

                    "image/jpeg".getBytes(), new byte[] {}, textBytes);

            return new NdefMessage(new NdefRecord[] { textRecord });

        }

    }

    // 写入tag

    boolean writeTag(NdefMessage message, Tag tag) {

        int size = message.toByteArray().length;

        try {

            Ndef ndef = Ndef.get(tag);

            if (ndef != null) {

                ndef.connect();

                if (!ndef.isWritable()) {

                    showToast("tag不允许写入");

                    return false;

                }

                if (ndef.getMaxSize() < size) {

                    showToast("文件大小超出容量");

                    return false;

                }

                ndef.writeNdefMessage(message);

                showToast("写入数据成功.");

                return true;

            } else {

                NdefFormatable format = NdefFormatable.get(tag);

                if (format != null) {

                    try {

                        format.connect();

                        format.format(message);

                        showToast("格式化tag并且写入message");

                        return true;

                    } catch (IOException e) {

                        showToast("格式化tag失败.");

                        return false;

                    }

                } else {

                    showToast("Tag不支持NDEF");

                    return false;

                }

            }

        } catch (Exception e) {

            showToast("写入数据失败");

        }

        return false;

    }

    private void showToast(String text) {

        Toast.makeText(this, text, Toast.LENGTH_SHORT).show();

    }

}

写入标签代码展开

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.sy.nfc.test"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="17" />

    <uses-permission android:name="android.permission.NFC" />

    <uses-feature

        android:name="android.hardware.nfc"

        android:required="true" />

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.sy.nfc.test.ReadTag"

            android:label="@string/app_name"

            android:launchMode="singleTop" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

            <intent-filter>

                <action android:name="android.nfc.action.TECH_DISCOVERED" />

            </intent-filter>

            <meta-data

                android:name="android.nfc.action.TECH_DISCOVERED"

                android:resource="@xml/nfc_tech_filter" />

        </activity>

        <activity android:name="com.sy.nfc.test.WriteTag" >

            <intent-filter>

                <action android:name="android.nfc.action.TAG_DISCOVERED" />

            </intent-filter>

        </activity>

    </application>

</manifest>

配置文件展开

已经非常详细了。源码下载：

http://download.csdn.net/detail/sy_hx/6307597

可以直接运行。主要就是NFC的读写实例。有需要的下载看看

点我下载

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