Android write to file not working

问题

I am a beginner when it comes to Android. I encountered a problem, regarding writing to a file. I want to save to a file the input I get in a form. However, the piece of code that I wrote is not writing in my file. Could anyone please help me? The code looks like that:

submit.setOnClickListener(new View.OnClickListener() {
     @Override
     public void onClick(View v) {
          StringBuilder s = new StringBuilder();
          s.append("Event name: " + editText1.getText() + "|");
          s.append("Date: " + editText2.getText() +  "|");
          s.append("Details: " + editText3.getText() + "|");

          File file = new File("D:\\config.txt");
          try {
              BufferedWriter out = new BufferedWriter(new FileWriter(file, true), 1024);
                out.write(s.toString());
                out.newLine();
                out.close();
           } catch (IOException e) {
                e.printStackTrace();
           }
      }
});

So, I have a form containing 3 fields: the name of an event, the date and the description. These I want to save to my file. I should mention that I use an emulator for testing.

回答1:

Use following path for file. It will write file to your root folder of storage.

String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
File file= new File(extStorageDirectory, "config.txt");

writeToFile("File content".getBytes(), file);

writeToFile

public static void writeToFile(byte[] data, File file) throws IOException {

    BufferedOutputStream bos = null;

    try {
        FileOutputStream fos = new FileOutputStream(file);
        bos = new BufferedOutputStream(fos);
        bos.write(data);
    }
    finally {
        if (bos != null) {
            try {
                bos.flush ();
                bos.close ();
            }
            catch (Exception e) {
            }
        }
    }
}

Don't forget to add following permission in AndroidManifest.xml

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

回答2:

https://github.com/rznazn/GPS-Data-Logger/blob/master/app/src/main/java/com/example/android/gpsdatalogger/StorageManager.java

Here is a... nearly complete class for writing to the documents folder on the emulated external storage of the device.

Don't forget to add the write permissions to manifest.

来源：https://stackoverflow.com/questions/44154767/android-write-to-file-not-working

标签

android

writetofile