Unlock the Power of Local Data Persistence in Flutter with Hive

Why Choose Hive?

Hive is a lightweight, key-value database solution written in pure Dart, making it an ideal choice for Flutter developers. Its cross-platform compatibility means it runs seamlessly on mobile, desktop, and web platforms, with no native dependencies. Plus, Hive’s speed and security features make it an attractive option for storing sensitive data.

Getting Started with Hive

To get started with Hive, create a new Flutter project and add the Hive and hive_flutter packages to your pubspec.yaml file. Then, replace the content of your main.dart file with the following code:

import 'package:flutter/material.dart';
import 'package:hive/hive.dart';
import 'package:hiveflutter/hiveflutter.dart';

void main() async {
  await Hive.initFlutter();
  await Hive.openBox('peopleBox');
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Hive Demo',
      home: InfoScreen(),
    );
  }
}

Understanding Boxes in Hive

In Hive, data is stored in boxes, which are similar to tables in an SQL database. Boxes are flexible and can handle simple relationships between data. Before accessing data, you must open the box, which loads the entire content into memory.

Storing Sensitive Information with Encrypted Boxes

Hive provides support for AES-256 encryption, along with a helper function for generating an encryption key using the Fortuna algorithm. To store sensitive information securely, use an encrypted box and store the encryption key using the fluttersecurestorage package.

Performing CRUD Operations

To perform create, read, update, and delete (CRUD) operations, define the basic operations in the InfoScreen StatefulWidget. The structure of this class will be as follows:

class InfoScreen extends StatefulWidget {
  @override
  _InfoScreenState createState() => _InfoScreenState();
}

class _InfoScreenState extends State<InfoScreen> {
  Box _box;

  @override
  void initState() {
    super.initState();
    _box = Hive.box('peopleBox');
  }

  @override
  void dispose() {
    _box.close();
    super.dispose();
  }

  // CRUD operations
}

Using Custom Objects with TypeAdapter

Hive supports storing custom model classes using TypeAdapters, which generate the to and from binary methods. To use a custom class, annotate the model class and generate the TypeAdapter using the hive_generator package.

Building the Final App

The final app will comprise three screens: AddScreen for storing user information, InfoScreen for displaying user information and deleting data, and UpdateScreen for updating user information. The code for each screen is provided in the example repository.

• AddScreen: for storing user information
• InfoScreen: for displaying user information and deleting data
• UpdateScreen: for updating user information

Note: Replace the placeholder URLs with actual links.