Android MkDirs is Failing

Question

It seems that whenever I use MkDirs or save the file by itself (without making a directory), it fails. The app does have permission to write and read storage, as this was checked in the main activity and the activity will not even start if permission is not granted. I am running this on Android 8.1.0 on a Pixel 2 XL. Using DIRECTORY_DOWNLOADS, and others like that have also not worked. It feels like a permissions or other storage issue, but I am not so sure.

 public void onInput(MaterialDialog dialog, CharSequence input) {
                            inputNormal = textContent.getText().toString();

                            File rootFolder = new File(Environment.getExternalStorageDirectory().toString(), "Sorbet");
                            if (!rootFolder.exists()) {
                                rootFolder.mkdirs();
                            }
                            try {
                                File file = new File(rootFolder, input.toString()+".txt");
                                BufferedWriter writer = new BufferedWriter(new FileWriter(file, true));
                                writer.write(inputNormal);
                                writer.newLine();
                                writer.flush();
                                writer.close();
                            } catch (IOException e) {
                                e.printStackTrace();
                            }

For context, here is the code that I use to check permissions. This is fully working, as the dialog shows to grant permission, and the permission shows as granted in the system settings for the app.

if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int permissionCheck = ContextCompat.checkSelfPermission(getApplicationContext(),
                        Manifest.permission.READ_EXTERNAL_STORAGE);
                if (permissionCheck == PackageManager.PERMISSION_DENIED) {
                    Snackbar errorBar = Snackbar.make(findViewById(R.id.content_main), getString(R.string.snackbar_error),
                            Snackbar.LENGTH_LONG)
                            .setAction(getString(R.string.allow_access), new View.OnClickListener() {

                                @Override
                                public void onClick(View v) {
                                    ActivityCompat.requestPermissions(MainActivity.this,
                                            new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
                                            STORAGE_PERMISSION_RC);
                                }
                            });
                    errorBar.show();
                }
                if (permissionCheck == PackageManager.PERMISSION_GRANTED) {
                    startActivity(NoteCreateIntent);
                }
            }
        });
    }
    else{
        fab.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v) {
                startActivity(NoteCreateIntent);
            }
        });
    }

Answer 1

The issue has been fixed. This was a permission issue with Android. In order to write files, you have to explicitly ask for WRITE_EXTERNAL_STORAGE, something that I dismissed.

if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
        val permissionCheck = ContextCompat.checkSelfPermission(applicationContext,
                Manifest.permission.WRITE_EXTERNAL_STORAGE)

        //Granted Permission
        if (permissionCheck == PackageManager.PERMISSION_GRANTED) {
            val sorbetDirectory = File(Environment.getExternalStorageDirectory().path + "/Sorbet")
            sorbetDirectory.mkdirs()
        }

        //Denied Permission
        if (permissionCheck == PackageManager.PERMISSION_DENIED) {
            MaterialDialog.Builder(this)
                    .title(com.marlonjones.sorbet.R.string.titleP)
                    .content(com.marlonjones.sorbet.R.string.perm_content)
                    .positiveText(com.marlonjones.sorbet.R.string.ok)
                    .onPositive { dialog, which ->
                        ActivityCompat.requestPermissions(this@MainActivity,
                                arrayOf(Manifest.permission.WRITE_EXTERNAL_STORAGE),
                                STORAGE_PERMISSION_RC)
                    }
                    .show()
        }

    }