在Android 中使用ContentObserver怎么获取短信验证码并实现自动填充

ContentObserver c=new ContentObserver(han) { 
        @Override 
        public void onChange(boolean selfChange) {           // TODO Auto-generated method stub 
          super.onChange(selfChange); 
          han.sendEmptyMessage(0); 
        } 
      }; 
getContentResolver().registerContentObserver(Uri.parse("content://sms"), true, c); 
Handler han = new Handler() { 
    @SuppressWarnings("deprecation") 
    public void handleMessage(android.os.Message msg) { 
      String codestr = null; 
      try { 
        codestr = Cus_UnitTools.getsmsyzm(Reg_ForgetPassword.this); 
        code.setText(codestr); 
        requestcode(); 
      } catch (Exception e) { 
        Log.e("yung", "验证码提取失败:" + codestr); 
      } 
    }; 
  };  
  public static String getsmsyzm(Activity c) { 
    Uri uri = Uri.parse("content://sms/inbox"); 
    String[] projection = new String[] { "address", "person", "body" }; 
    String selection = " address='" + JTPHONE + "' "; 
    String[] selectionArgs = new String[] {}; 
    String sortOrder = "date desc"; 
    @SuppressWarnings("deprecation") 
    Cursor cur = c.managedQuery(uri, projection, selection, selectionArgs, 
        sortOrder); 
    if(cur!=null&&cur.getCount()>0){ 
      cur.moveToFirst(); 
      String body = cur.getString(cur.getColumnIndex("body")).replaceAll( 
          "\n", " "); 
      cur.close(); 
      return getyzm(body, YZMLENGTH); 
  } 
    cur.close(); 
    return null; 
  } 
    /** 
   * 从短信字符窜提取验证码 
   * @param body 短信内容 
     * @param YZMLENGTH 验证码的长度 一般6位或者4位 
   * @return 接取出来的验证码 
   */ 
  public static String getyzm(String body, int YZMLENGTH) { 
    // 首先([a-zA-Z0-9]{YZMLENGTH})是得到一个连续的六位数字字母组合 
    // (&#63;<![a-zA-Z0-9])负向断言([0-9]{YZMLENGTH})前面不能有数字 
    // (&#63;![a-zA-Z0-9])断言([0-9]{YZMLENGTH})后面不能有数字出现 
    Pattern p = Pattern 
        .compile("(&#63;<![a-zA-Z0-9])([a-zA-Z0-9]{" + YZMLENGTH + "})(&#63;![a-zA-Z0-9])"); 
    Matcher m = p.matcher(body); 
    if (m.find()) { 
      System.out.println(m.group()); 
      return m.group(0); 
    } 
    return null; 
  } 
//有些验证码是纯数字的那么直接用这个就可以了
//Pattern p = Pattern.compile("(&#63;<![0-9])([0-9]{" + YZMLENGTH+ "})(&#63;![0-9])");

 <!-- 发送短信-->
  <uses-permission Android:name="android.permission.SEND_SMS" />
  <!-- 阅读消息 -->
  <uses-permission android:name="android.permission.READ_SMS" />
  <!-- 写入消息 -->
  <uses-permission android:name="android.permission.WRITE_SMS" />
  <!-- 接收消息 -->
  <uses-permission android:name="android.permission.RECEIVE_SMS" />