Introduction
A while ago, I posted a post about how to store key-value data using shared_preferences package.
However, shared_preferences is not pure Dart and depends on the platform, which might not be a good performance choice. So, I decided to look for another approach, and I found hive.
After using the package for several projects, I grew tired of writing/copying boilerplate code just to store my key-value data. I came up with an idea of writing a wrapper package for hive. This package should meet these criteria:
- Support data encryption
- Support Lazy loading of data
- Support store data using Enum key
- Support Listenable
- And be EASY to use.
Links
- pub.dev: https://pub.dev/packages/easy_hive
- GitHub: https://github.com/simonpham/easy_hive
Guide to use:
You can either define your boxes as Singleton classes or use a service locator like
get_it.
Let's take a look at the guide to define a simple SettingsBox to store your settings using singleton class approach.
1. Define box keys 🔑
enum Settings {
key, // Use as box key. You can use a String constant instead.
/// Other keys below...
themeMode,
counter,
}
2. Define a box 📦
import 'package:easy_hive/easy_hive.dart';
class SettingsBox extends EasyBox {
@override
String get boxKey => Settings.key.toString();
/// Singleton.
static final SettingsBox _instance = SettingsBox._();
factory SettingsBox() => _instance;
SettingsBox._();
}
3. Initialize box 🚀
import 'package:easy_hive/easy_hive.dart';
Future<void> main() async {
await EasyBox.initialize();
await SettingsBox().init();
// runApp...
}
4. Define getter & setter for your data 💄
extension GeneralSettingsExtension on SettingsBox {
ThemeMode get themeMode {
final index = get(
Settings.themeMode,
defaultValue: 0,
);
return ThemeMode.values[index];
}
set themeMode(ThemeMode value) => put(Settings.themeMode, value.index);
int get counter => get(Settings.counter, defaultValue: 0);
set counter(int value) => put(Settings.counter, value);
}
5. Use it anywhere 🔥
Text(
'You have pushed: ${SettingsBox().counter} times.',
style: Theme.of(context).textTheme.headlineMedium,
),
FilledButton(
onPressed: () {
SettingsBox().counter++;
},
child: Text('Increment'),
),
FilledButton(
onPressed: () {
SettingsBox().themeMode = ThemeMode.dark;
},
child: Text('Dark Theme'),
),
Advanced Usage 😈
Enable encryption 🔐
1. Install easy_hive_encryption:
2. Add EncryptionMixin to your box class:
class SettingsBox extends EasyBox with EncryptionMixin {
@override
String get boxKey => Settings.key.toString();
/// Override encryption key name (optional).
@override
String get encryptionKeyName => "your-own-key-name";
}
3. Follow flutter_secure_storage's guide for specific platform setup.
Enable lazy loading 🐢
1. Add LazyMixin to your box class:
class SettingsBox extends EasyBox with LazyMixin {
@override
String get boxKey => Settings.key.toString();
}
2. Use await to get your value:
extension GeneralSettingsExtension on SettingsBox {
Future<ThemeMode> getThemeMode() async {
final index = await get(
Settings.themeMode,
defaultValue: 0,
);
return ThemeMode.values[index];
}
}
Listen to value changes 🎧
Recommended: Use RefreshableBox + provider:
1. Extends RefreshableBox instead of EasyBox:
class SettingsBox extends RefreshableBox {
@override
String get boxKey => Settings.key.toString();
}
2. Use it as a provider:
ChangeNotifierProvider(
create: (_) => SettingsBox(),
child: SomeWidget(),
),
// Inside SomeWidget.
Text(
'You have pushed: '
'${context.select((SettingsBox _) => _.counter)} times.',
),
For more info, see provider package.
Or if you don't want RefreshableBox:
Just use ValueListenableBuilder to listen to changes.
ValueListenableBuilder(
valueListenable: [
Settings.counter,
].of(SettingsBox()),
builder: (context, _, __) {
return Text(
'${SettingsBox().counter}',
);
},
),
This guide is taken from easy_hive repository.
Top comments (0)