private static final String FILE_FOLDER =
  Environment.getExternalStorageDirectory().getAbsolutePath()
  + File.separator + "AboutView" + File.separator + "data";
private static final String FILE_CSV = "about_data.csv";

class WriteData2CSVThread extends Thread {
  short[] data;
  String fileName;
  String folder;
  StringBuilder sb;
  public WriteData2CSVThread(short[] data, String folder, String fileName) {
   this.data = data;
   this.folder = folder;
   this.fileName = fileName;
  }
  private void createFolder() {
   File fileDir = new File(folder);
   boolean hasDir = fileDir.exists();
   if (!hasDir) {
    fileDir.mkdirs();// 这里创建的是目录
   }
  }
  @Override
  public void run() {
   super.run();
   createFolder();
   File eFile = new File(folder + File.separator + fileName);
   if (!eFile.exists()) {
    try {
     boolean newFile = eFile.createNewFile();
    } catch (IOException e) {
     e.printStackTrace();
    }
   }
   try {
    FileOutputStream os = new FileOutputStream(eFile, true);
    sb = new StringBuilder();
    for (int i = 0; i < data.length; i++) {
     sb.append(data[i]).append(",");
    }
    sb.append("\n");
    os.write(sb.toString().getBytes());
    os.flush();
    os.close();
   } catch (Exception e) {
    e.printStackTrace();
   }
  }
 }

class ReadCSVThread extends Thread {
  String fileName;
  String folder;
  public ReadCSVThread(String folder, String fileName) {
   this.folder = folder;
   this.fileName = fileName;
  }
  @Override
  public void run() {
   super.run();
   File inFile = new File(folder + File.separator + fileName);
   final StringBuilder cSb = new StringBuilder();
   String inString;
   try {
    BufferedReader reader =
     new BufferedReader(new FileReader(inFile));
    while ((inString = reader.readLine()) != null) {
     cSb.append(inString).append("\n");
    }
    reader.close();
   } catch (Exception e) {
    e.printStackTrace();
   }
   runOnUiThread(new Runnable() {
    @Override
    public void run() {
     mCSVTv.setText(cSb.toString());// 显示
    }
   });
  }
 }