android nfc NDEF的RTD_TEXT读写

       android nfc 有两种读写模式，分别是NDEF读写模式与非NDEF读写模式，非NDEF读写模式中又有一下几种：

IsoDep、MifareClassic、MifareUltralight、Ndef、ndefFormtable、Nfca、Nfcb、NfcBarcode、NfcF、NfcV（通过Tag.getTechlist（）获得）。

       主要讲的是NDEF格式的读写，测试demo地址如下：

       http://download.csdn.net/detail/u012303938/9292897

     代码如下

package com.example.ndefreadwrite;

import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.Locale;

import android.support.v7.app.ActionBarActivity;
import android.app.PendingIntent;
import android.content.Intent;
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.AsyncTask;
import android.os.Bundle;
import android.os.Parcelable;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.CheckBox;
import android.widget.TextView;
import android.widget.Toast;


public class MainActivity extends ActionBarActivity {
  CheckBox checkBox1;
  TextView textView1;
  NfcAdapter nfcAdapter;
  PendingIntent  intent;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        checkBox1=(CheckBox) findViewById(R.id.checkBox1);
        textView1=(TextView) findViewById(R.id.textView1);
        intent=PendingIntent.getActivity(this, 0, new Intent(this,getClass()), 0);
        nfcAdapter=NfcAdapter.getDefaultAdapter(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
    
    @Override
    	protected void onResume() {
    		// TODO Auto-generated method stub
    		super.onResume();
    		nfcAdapter.enableForegroundDispatch(this, intent, null, null);
    	}
    @Override
    	protected void onPause() {
    		// TODO Auto-generated method stub
    		super.onPause();
    		nfcAdapter.disableForegroundDispatch(this);
    	}
    @Override
    	protected void onNewIntent(Intent intent) {
    		// TODO Auto-generated method stub
    		super.onNewIntent(intent);
    		Toast.makeText(this, intent.getAction(), 1).show();
    		if(NfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())){
    			
    			Tag tag=intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
    			Parcelable []parcelables= intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
    		    if(checkBox1.isChecked()){
    		    	NdefMessage message=getNdefTextMsg("123456789", true, true);
    		    	MyTask myTask=new MyTask(message, tag);
    		    	myTask.execute(null,null,null);
    		    }else{
    		    	readMsg(parcelables);
    		    }
    			
    		}
    		
    	}
    
        public void readMsg(Parcelable []parcelables){
        	NdefMessage ndefMessages[]=null;
        	if(parcelables!=null){
        		StringBuilder builder=new StringBuilder();
        		ndefMessages=new NdefMessage[parcelables.length];
            	for(int i=0;i{
    	NdefMessage message;
    	Tag tag;
    	String text="";
    	
    	public MyTask(NdefMessage message,Tag tag) {
			// TODO Auto-generated constructor stub
    		this.message=message;
    		this.tag=tag;
		}

		@Override
		protected Object doInBackground(Object... params) {
			// TODO Auto-generated method stub
			int size=message.toByteArray().length;
			try {
				Ndef ndef=Ndef.get(tag);
				if(ndef==null){
					NdefFormatable formatable=NdefFormatable.get(tag);
					if(formatable!=null){
						try {
							formatable.connect();
						    try {
							formatable.format(message);	
							} catch (Exception e) {
								// TODO: handle exception
								text="格式化失败";
							}
							
						} catch (Exception e) {
							// TODO: handle exception
							text="格式化连接失败";
						}finally{
							formatable.close();
						}
					}else{
						text="这不是ndef标签,不能格式化";
					}
				}else{
					ndef.connect();
					try {
						if(!ndef.isWritable()){
							text="该ndef标签不能写入";
						}else if(ndef.getMaxSize()