Solid Shared Preference For Flutter (A statically typed wrapper around the shared_preference package)

Description

With Solid Shared Preference, you can declare your preference once in a top level file and forget about its key and type. It remembers its type and key. So, your change of making mistake is zero. It even understands the difference between nullable and non-nullable types. By default, the value of Preference is non-nullable.

We recommand a single global constant for a single preference but it is also okay to create a local preference.

Usage

• Add the followinf line to your pubspec.yaml

solid_shared_pref: ^0.0.5

• import the package in your main.dart file

import 'package:solid_shared_pref/solid_shared_pref.dart';

• Make your main function async and call the followinf two functions before runApp:

  WidgetsFlutterBinding.ensureInitialized();
  await initSolidSharedPreferences();

Full main function can be this:

void main() async{
  /// we initialize the solid shared preference here
  WidgetsFlutterBinding.ensureInitialized();
  await initSolidSharedPreferences();
  runApp(const MyApp());
}

• Create a preference variable/constant (We recommand creating a constant whenever possible). As the preference object only contains the key and default values, creating constant wont affect preference values (It will improve performance).
• Cretae a file to store all the top level constants/variables. So you can access them across the app.
• Creating a preference that holds an integer value:

const counterPreference = IntPreference('my_counter', 0);
// IntPreference(key, defaultValue);

• Reading its value:

final counter = counterPreference.value;

• Updating its value:

counterPreference.value++;

• Setting the value to null will give us a compile time error since the preference is not nullable. To use a nullablePreference use a NullableIntPreference object;

 counterPreference.value = null; /// compile time error
 const nullableCounter = NullableIntPreference('my_nullable_counter', 0);
 nullableCounter = null;  /// okay

• Removing a value:

counterPreference.remove();

• Creating a shared Preference of a Custom object:

final jokeMetadata = CustomPreference<JokeMetadata>(
    'joke_metadata', JokeMetadata.defaultValue(),
    fromJson: (json) => JokeMetadata.fromJson(json),
    toJson: (metadata) => metadata.toJson);
	// CustomPreference(key, defaultValue , {fromJson, toJson});

• fromJson: A function that takes a Map<String, dynamic>and returns the Object
• toJson: A function that takes an object adn returns a Map<String, dyamic>?

You can now enjoy all the functions of a premetice pregerence for your own custom class.