Flutter: Appending / streaming data to secure storage item

Question

I am developing an app in Flutter that loads files from a server and saves them to secure local storage for later offline use.

I am running into issues with larger documents (e.g. a 150megs PDF), resulting in OutOfMemoryError s on Android.

Is there a way to "append" bytes to a secure storage item or have something like a streaming approach?

Thanks!

Update: I am using the "flutter_secure_file_storage" package.

import 'package:flutter_secure_file_storage/flutter_secure_file_storage.dart';

final localStorageManager = LocalStorageManager._(
    FlutterSecureFileStorage(const FlutterSecureStorage()));

class LocalStorageManager {
  final LocalStorageItemMap<DocumentContent> documentContents;
  
  LocalStorageManager._(FlutterSecureFileStorage secureStorage)
      : storageVersion =
            LocalStorageItem(secureStorage, key: "storage_version"),
        settings = LocalStorageSettingsItems._(secureStorage),
        login = LocalStorageLoginItems._(secureStorage),
        documentContents =
            LocalStorageItemMap(secureStorage, "document_contents_");