Write txt file in Android

        // get the path to sdcard
        File sdcard = Environment.getExternalStorageDirectory();
        // to this path add a new directory path
        File dir = new File(sdcard.getAbsolutePath() + "/thieumao/");
        // create this directory if not already created
        dir.mkdir();
        // create the file in which we will write the contents
        File file = new File(dir, "name.txt");
        FileOutputStream os;
        try {
            os = new FileOutputStream(file);
            String data = "Messages";
            try {
                os.write(data.getBytes());
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                os.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }