Persisting todo items

[SimonLab]

The PR #17 focused on explaining how to create a simple UI with the Flutter widgets. However it doesn't explain yet how to persist the items created while the application is running.
We want to describe what are the different way to store/save data and load the information when the application is reopened.

• Simple key-value store system using the shared_preferences package. As our data is a bit more complex that just a key-value we will need first to convert the item objects to json and serialised (convert to string) them to be able to save them. Persiting items using shared_preferences #21
• Database system with SQLite. see: drift reactive persistence library for Flutter & Dart built on top of sqlite learn-flutter#70
• API system where we can save the items using a (Phoenix) REST API. We can also see how to use Phoenix Channels with Flutter, this can be useful when creating collaborative todo list for example. Dependent on: Feat: Todo List REST API phoenix-todo-list-tutorial#53

see also https://flutter.dev/docs/cookbook/persistence

[nelsonic]

@SimonLab how long would it take to upgrade https://github.com/dwyl/phoenix-todo-list-tutorial to have a basic API that would allow Flutter to GET/POST to use it as a Backend? 💭

[SimonLab]

@nelsonic I don't think it should take too long to add and it can be nice to see the API used with Flutter

[nelsonic]

Please See: dwyl/phoenix-todo-list-tutorial#53

[nelsonic]

@SimonLab can we consider this done? 💭
This tutorial is using riverpod:

flutter-todo-list-tutorial/pubspec.yaml

Line 41 in 575a8ba

flutter_riverpod: ^2.1.1