java - 以文本文件形式保存到 SD 卡

Question

   stopWriting = (Button) findViewById(R.id.save);
   stopWriting.setOnClickListener(new OnClickListener() {

       @SuppressLint("SdCardPath")
    public void onClick(View v) {
           // stop recording the sensor data
           try {

               myFile = new File("/sdcard/SensorData/" + txtData.getText() + ".txt");
               myFile.createNewFile();

               sData = new FileOutputStream(myFile);
               myOutWriter = new OutputStreamWriter(sData);
               myBufferedWriter = new BufferedWriter(myOutWriter);
               myPrintWriter = new PrintWriter(myBufferedWriter);

               //if(myFile != null )//stopFlag = mSensorManager.cancelTriggerSensor(null, null);
               Toast.makeText(getBaseContext(), "Done", Toast.LENGTH_SHORT).show();
           } catch (Exception e) {
               Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
           }
       }
   });

我正在尝试将陀螺仪数据保存到 txt 文件，但它没有保存。如果有人发现问题，请帮我改正。

Answer 1

试试这段代码:

public  void writeToFile(String fileName, String body)
    {
        FileOutputStream fos = null;

        try {
            final File dir = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/folderName/" );

            if (!dir.exists())
            {
                     if(!dir.mkdirs()){
                         Log.e("ALERT","could not create the directories");
                     }
            }

            final File myFile = new File(dir, fileName + ".txt");

            if (!myFile.exists()) 
            {    
                myFile.createNewFile();
            } 

            fos = new FileOutputStream(myFile);

            fos.write(body.getBytes());
            fos.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

此外，请记住在您的 list 文件中包含外部存储权限:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

在 android 6.0 上请求 WRITE_EXTERNAL_STORAGE 权限