shared_preferences_gen #

A code generator that provides strongly-typed accessors for Flutter shared_preferences entries.

Features #

• Check for duplicate keys
• Type-safe accessors for shared preferences
• Support for:
  • DateTime
  • enum
  • Serializable objects with fromJson constructor and toJson method

How to use #

Install #

Make sure to add these packages to the project dependencies:

flutter pub add --dev build_runner
flutter pub add --dev shared_preferences_gen
flutter pub add shared_preferences_annotation

Compatibility with json_serializable #

If you are using json_serializable, you need to add the following configuration to your build.yaml file:

global_options:
  json_serializable:
    runs_before:
      - shared_preferences_gen

This will ensure that the generated toJson and fromJson methods are available when analyzing the code.

Add imports and part directive #

Make sure to specify the correct file name in a part directive. In the example below, replace "name" with the file name.

import 'package:shared_preferences_annotation/shared_preferences_annotation.dart';

part 'name.g.dart';

Run the code generator #

To run the code generator, run the following commands:

dart run build_runner build --delete-conflicting-outputs

Create a shared preferences entry #

To create a shared preferences entry, first create an annotation @SharedPrefData in the file where you want to store your instance of SharedPreferences. Then add an entry with its corresponding type, key and default value (optional).

SharedPrefEntry #

A SharedPrefEntry can be used with any of those types:

• bool
• double
• int
• String
• List<String>
• DateTime
• Any enum
• Any serializable object with a toJson method and fromJson factory constructor

@SharedPrefData(entries: [
  SharedPrefEntry<String>(key: 'myKey'),
])
void main() { /* ... */ }

Read an entry #

You can access the generated entries directly from your instance of SharedPreferences.

final prefs = await SharedPreferences.getInstance();
String myKey = prefs.myKey.value;
bool darkMode = prefs.darkMode.value;

Write an entry #

final prefs = await SharedPreferences.getInstance();
await prefs.myKey.setValue('newValue');

Remove an entry #

final prefs = await SharedPreferences.getInstance();
await prefs.myKey.remove();

Roadmap #

• Support for custom objects (no ETA)