FLUTTER- How to save a List<Object> into shared Preferences? - json

Question

I want to add a product to cart and save it, so that when i open the app again, it is present in the cart. i can add multiple products to cart, so I am looking to save a List<Products>
I want to save a List into sharedPreferences and retrieve the same, but there are no methods for that. I tried using setStringList but I am unable to convert the string into object. And the data is not getting saved also.
my class model-
import 'dart:convert';
class Products {
Products({
required this.title,
required this.price,
required this.description,
required this.image,
this.quantity = 0,
});
final String title;
final double price;
final String description;
final String image;
int quantity;
factory Products.fromRawJson(String str) =>
Products.fromJson(json.decode(str));
String toRawJson() => json.encode(toJson());
factory Products.fromJson(Map<String, dynamic> json) => Products(
title: json["title"],
price: json["price"].toDouble(),
description: json["description"],
image: json["image"],
);
Map<String, dynamic> toJson() => {
"title": title,
"price": price,
"description": description,
"image": image,
};
}

Answer 1

The shared_preferences library has only the options to save the following.
int
string
List
double
boolean
Reference:
https://pub.dev/documentation/shared_preferences/latest/shared_preferences/SharedPreferences-class.html
But what you could do is to create a List<String> in their jsonEncode form and save it.
Convert the List to List by encoding each of them using https://api.flutter.dev/flutter/dart-convert/jsonEncode.html
Once done you can save it and while decoding it similarly use jsonDecode
Hope this helps.
Thanks!

Answer 2

import 'dart:convert';
//first converts your array to json string store it in session
String strJsonString = json.encode(arrayProducts);
//save strJsonString as String into your session
//when you want to retrive it from session just decode session value
List<Products> = json.decode(strJsonString);