苦苦挣扎于 Scoped Storage - 如何在 Java 的 app 目录中编写纯文本文件？

Question

I am migrating our apps to API version 30, and I am totally struggling with Scoped Storage. I would like to know, how would I write a plain text file in the app directory using Scoped Storage? I am currently using FileWriter and I would like to know how I would change this to Scoped Storage. I would like my example in Java, not Kotlin, please.

Answer 1

Use the location

context.getFilesDir()+"/YourFolderName";

Here you can store any file you want without any permission, If you want to store Document file where its publically available, Use this location, you dont need any permission over here either

  try {
        inputStream = //your input stream here;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }


    ContentResolver resolver = ctx.getContentResolver();
    ContentValues values = new ContentValues();

    values.put(MediaStore.MediaColumns.DISPLAY_NAME, "My Document name");
        values.put(MediaStore.MediaColumns.MIME_TYPE,"application/*");


    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOCUMENTS + File.separator + "my app folder/");
    }

    Uri fileUri = resolver.insert(MediaStore.Files.getContentUri("external"), values);      
    try {
        fos = resolver.openOutputStream(fileUri);
        Objects.requireNonNull(fos);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    try {
        byte[] buf = new byte[1024];
        int len;
        while ((len = inputStream.read(buf)) > 0) {

            fos.write(buf, 0, len);
        }

        fos.close();
        inputStream.close();
        fos.flush();
        fos.close();
    } catch (Exception e) {
        Log.d("TAG", "Exception" + e.getMessage());
        e.printStackTrace();
    }

I included the code for the second method bcz i felt like "MediaStore" might confuse you!