我試圖將一個(gè)簡單的XML文件簡單地寫入SD卡，但我注意到Nexus 4確實(shí)寫入了該文件，但是使用Windows 7不能通過MTP協(xié)議查看該文件。碼：public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    CustomerQueryRqType customerQueryRequest = new CustomerQueryRqType();    Serializer serializer = new Persister();    File myFile = new File(Environment.getExternalStorageDirectory() + "/customerQueryRequest.xml");    try {        boolean created = myFile.createNewFile();        serializer.write(customerQueryRequest, myFile);    } catch (Exception e) {        e.printStackTrace();    }}我可以使用Astro File Manager在手機(jī)上看到文件：但是Windows看不到...：adb shell 在目錄上顯示：ls -ldrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Alarmsdrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Androiddrwxrwxr-x root     sdcard_rw          2012-11-21 19:30 DCIMdrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Downloaddrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Moviesdrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Musicdrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Notificationsdrwxrwxr-x root     sdcard_rw          2012-11-19 12:06 Picturesdrwxrwxr-x root     sdcard_rw          1970-01-16 20:51 Podcastsdrwxrwxr-x root     sdcard_rw          2012-11-19 13:22 Ringtonesdrwxrwxr-x root     sdcard_rw          2012-11-19 14:33 bluetooth-rw-rw-r-- root     sdcard_rw       79 2012-12-05 22:26 customerQueryRequest.xmldrwxrwxr-x root     sdcard_rw          2012-11-20 02:50 data-rw-rw-r-- root     sdcard_rw    11394 2012-11-19 13:54 eightpen_custom_gesturesdrwxrwxr-x root     sdcard_rw          2012-11-19 13:17 mediaNexus 4怎么了？為什么要在Windows中隱藏我的東西？