easy_prefs_gen

Description:

easy prefs gen

Flutter code generator for generating easy-to-use shared_preferences.


Running the code generator
Example
PrefsAnnotation

Parameters
PrefsStringList



Setup #
Add easy_prefs and shared_preferences to dependencies, easy_prefs_gen and build_runner to dev_dependencies.
Note: Add provider as well if you're going to use [PrefsAnnotation] with [providerExtensionMethods] set to true.
dependencies:
easy_prefs: [version]
shared_preferences: ^2.0.11

dev_dependencies:
build_runner: [version]
easy_prefs_gen: [version]
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in your main.dart file
// IMPORT THESE TWO PACKAGES
import 'package:easy_prefs/easy_prefs.dart';
import 'package:shared_preferences/shared_preferences.dart';

Future<void> main() async {
// ADD THESE TWO LINES
WidgetsFlutterBinding.ensureInitialized();
await EasyPrefs.initialize(await SharedPreferences.getInstance());

// ..

runApp(const MyApp());
}
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Running the code generator #
Once you have added the annotations to your code you then need to run the code
generator to generate the missing .g.dart generated dart files.
flutter pub run build_runner build

// or watch
flutter pub run build_runner watch
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Example #
Given a dart file example.dart with an Settings class annotated with [PrefsAnnotation]:

import 'package:easy_prefs/easy_prefs.dart';
import 'package:flutter/material.dart'; // or cupertiono, this is required if [changeProvider] is set to true
import 'package:provider/provider.dart'; // this is required if [providerExtensionMethods] is set to true

part 'example.g.dart';

@PrefsAnnotation(
{
"username": "",
"notification": true,
"notificationSound": true,
"exchangeRate": 1.1,
"language": LanguageCodes.kmr,
"likeCount": 0,
"favs": PrefsStringList(["asf", "afsaf"]),
"favs2": ["asf", "afsaf"],
},
changeNotifier: true,
onlyModifier: true,
providerExtensionMethods: true,
toggleMethodForBoolValues: true,
)
class Settings extends _$Settings {}
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Building creates the corresponding part example.g.dart:
// GENERATED CODE - DO NOT MODIFY BY HAND

part of 'example.dart';

// **************************************************************************
// PrefsGenerator
// **************************************************************************

class _PrefKeysForSettings {
const _PrefKeysForSettings();
final String username = 'username';
final String notification = 'notification';
final String notificationSound = 'notificationSound';
final String exchangeRate = 'exchangeRate';
final String language = 'language';
final String likeCount = 'likeCount';
final String favs = 'favs';
final String favs2 = 'favs2';
}

class _$Settings with IEasyPrefs, ChangeNotifier {
final _helper = SharedPreferencesHelper();
final _keys = const _PrefKeysForSettings();

/// if [silent] is true, value changes won't be notified.
_$Settings({bool silent = false}) {
if (silent) return;
_helper.onNotify = onValueChanged;
}

@override
void onValueChanged(String key) {
notifyListeners();
}

String? _$username;
String get username => _$username ?? _helper.getString(_keys.username, '');
set username(String val) => _helper.setString(_keys.username, val, (_) => _$username = val);

bool? _$notification;
bool get notification => _$notification ?? _helper.getBool(_keys.notification, true);
set notification(bool val) => _helper.setBool(_keys.notification, val, (_) => _$notification = val);
bool toggleNotification() => _helper.toggleBool(_keys.notification, true, (val) => _$notification = val);

bool? _$notificationSound;
bool get notificationSound => _$notificationSound ?? _helper.getBool(_keys.notificationSound, true);
set notificationSound(bool val) => _helper.setBool(_keys.notificationSound, val, (_) => _$notificationSound = val);
bool toggleNotificationSound() => _helper.toggleBool(_keys.notificationSound, true, (val) => _$notificationSound = val);

double? _$exchangeRate;
double get exchangeRate => _$exchangeRate ?? _helper.getDouble(_keys.exchangeRate, 1.1);
set exchangeRate(double val) => _helper.setDouble(_keys.exchangeRate, val, (_) => _$exchangeRate = val);

LanguageCodes? _$language;
LanguageCodes get language => _$language ?? _helper.getEnum(_keys.language, LanguageCodes.values, LanguageCodes.kmr);
set language(LanguageCodes val) => _helper.setInt(_keys.language, val.index, (_) => _$language = val);

int? _$likeCount;
int get likeCount => _$likeCount ?? _helper.getInt(_keys.likeCount, 0);
set likeCount(int val) => _helper.setInt(_keys.likeCount, val, (_) => _$likeCount = val);

NotifiableStringList? _$favs;
NotifiableStringList get favs => _$favs ?? _helper.getStringList(_keys.favs, ['asf', 'afsaf']);
set favs(NotifiableStringList val) => _helper.setStringList(_keys.favs, val, (_) => _$favs = val);

NotifiableStringList? _$favs2;
NotifiableStringList get favs2 => _$favs2 ?? _helper.getStringList(_keys.favs2, ['asf', 'afsaf']);
set favs2(NotifiableStringList val) => _helper.setStringList(_keys.favs2, val, (_) => _$favs2 = val);

@override
void initializeAll() {
final _tmp = _helper.onNotify;
_helper.onNotify = null;

username = username;
notification = notification;
notificationSound = notificationSound;
exchangeRate = exchangeRate;
language = language;
likeCount = likeCount;
favs = favs;
favs2 = favs2;

_helper.onNotify = _tmp;
_helper.onNotify?.call("");
}

@override
bool isTouched() {
return _helper.hasKey(_keys.username) ||
_helper.hasKey(_keys.notification) ||
_helper.hasKey(_keys.notificationSound) ||
_helper.hasKey(_keys.exchangeRate) ||
_helper.hasKey(_keys.language) ||
_helper.hasKey(_keys.likeCount) ||
_helper.hasKey(_keys.favs) ||
_helper.hasKey(_keys.favs2);
}

@override
String toString() {
return '''
{
"username" : "$username",
"notification" : $notification,
"notificationSound" : $notificationSound,
"exchangeRate" : $exchangeRate,
"language" : $language,
"likeCount" : $likeCount,
"favs" : [
${favs.map((e) => '"$e"').join(",\n ")}
],
"favs2" : [
${favs2.map((e) => '"$e"').join(",\n ")}
]
}
''';
}
}

extension SettingsProviderExtensionMethodsOnBuildContext on BuildContext {
Settings readSettings() => read<Settings>();
Settings watchSettings() => watch<Settings>();
R selectSettings<R>(R Function(Settings s) selector) => select(selector);
}

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Consuming the class main.dart (Hier I used provider for state management)
import 'package:easy_prefs/easy_prefs.dart';
import 'package:easy_prefs_example/settings.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:shared_preferences/shared_preferences.dart';

Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized(); // IMPORTANT
await EasyPrefs.initialize(await SharedPreferences.getInstance()); // IMPORTANT
runApp(const MyApp());
}

class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);

@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'EasyPrefs Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: ChangeNotifierProvider(
create: (_) => Settings(),
builder: (_, __) {
return const MyHomePage();
},
),
);
}
}

class MyHomePage extends StatelessWidget {
const MyHomePage({Key? key}) : super(key: key);

@override
Widget build(BuildContext context) {
final settings = context.watchSettings();
final lastValInFavList = int.parse(settings.favs.isNotEmpty ? settings.favs.last : "0");
return Scaffold(
appBar: AppBar(
title: const Text("EasyPrefs Demo"),
),
body: Padding(
padding: const EdgeInsets.all(8.0),
child: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
CheckboxListTile(
value: settings.notification,
title: const Text("Enable notification"),
onChanged: (t) => settings.notification = t!,
),
CheckboxListTile(
value: settings.notificationSound,
title: const Text("Enable notification sound"),
onChanged: (t) => settings.notificationSound = t!,
),
const Divider(height: 1),
ListTile(
title: const Text("Language"),
trailing: DropdownButton(
value: settings.language,
items: LanguageCodes.values
.map((e) => DropdownMenuItem(
child: Text(e.name, textScaleFactor: 1.2),
value: e,
))
.toList(),
onChanged: (LanguageCodes? lang) {
if (lang != null) {
settings.language = lang;
}
},
),
),
const Divider(height: 1),
Row(
children: [
const Padding(
padding: EdgeInsets.all(16.0),
child: Text("View Count: ", textScaleFactor: 1.2),
),
const Spacer(),
IconButton(onPressed: () => settings.likeCount--, icon: const Icon(Icons.remove)),
Text(settings.likeCount.toString(), textScaleFactor: 1.2),
IconButton(onPressed: () => settings.likeCount++, icon: const Icon(Icons.add)),
],
),
const Divider(height: 1),
Row(
children: [
const Padding(
padding: EdgeInsets.all(16.0),
child: Text("Fav Items: ", textScaleFactor: 1.2),
),
const Spacer(),
ElevatedButton(onPressed: () => settings.favs.removeLast(), child: const Icon(Icons.remove)),
const SizedBox(width: 5),
ElevatedButton(onPressed: () => settings.favs.add("${lastValInFavList + 1}"), child: const Icon(Icons.add)),
],
),
const Divider(height: 20),
const Padding(
padding: EdgeInsets.fromLTRB(20, 10, 20, 0),
child: Text("settings.toString() :", textScaleFactor: 1.1),
),
Padding(
padding: const EdgeInsets.fromLTRB(20, 5, 20, 10),
child: Text(settings.toString()),
),
],
),
),
),
);
}
}

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PrefsAnnotation #
Parameters #
PrefsStringList #