How to Migrate Flutter Bloc from Version 6 to 8

TL;DR

To migrate Flutter Bloc from version 6 to version 8, update all dependencies using the Pubspec assist extension and replace deprecated classes with BlocOverrides.runZoned. Implement a custom BlocObserver and use HydratedBlocObserver to manage local data storage. The migration involves adjusting for null safety and ensuring proper functionality of your app features.

Transcript

hi there in this tutorial we are going to  migrate flutter block from version 6 to   version 8 which is currently the latest one. The  link of the source code is in the description,   like the video, subscribe and don't miss my future  real projects. Here are all dependencies. Now   let's introduce our litter counter project that  uses MultiBlocPro... Read More

Key Insights

• ❓ Flutter Bloc version 8 can be easily updated by using the Pubspec assist extension to update all dependencies at once.
• 😀 The sample app showcases various features like counter management, connectivity detection, and local data storage.
• 🏛️ Migrating from version 6 to 8 involves updating the custom BlocObserver class and using BlocOverrides.runZoned instead of Bloc.observer in the main class.

Questions & Answers

Q: How can I update my Flutter Bloc from version 6 to version 8?

To update the Flutter Bloc, you can use the Pubspec assist extension to easily update or add new dependencies. Once updated, run 'flutter pub get' to fetch the latest versions of the dependencies.

Q: What features are showcased in the sample app?

The sample app demonstrates a counter that can be increased and decreased. It also includes connectivity detection, where the counter value changes based on the network connection type. Additionally, there's a settings page and the ability to debug Bloc and Cubit states using BlocOverrides and blocOverrides.

Q: How can I implement local data storage using HydratedBlocObserver?

To store data locally, you can use the HydratedBlocObserver and its storage feature. It allows you to persist and restore bloc states across app restarts. Implement the HydratedBlocObserver and configure it to use the desired storage mechanism.

Q: What changes are required in the main class for BlocObserver?

Instead of using Bloc.observer, which is deprecated, you should use BlocOverrides.runZoned in the main class. This ensures that the observer is correctly applied to your app's Blocs.

Summary & Key Takeaways

• The tutorial explains how to update a Flutter Bloc from version 6 to the latest version 8, with the source code provided.

• A sample app is introduced, featuring a counter that can be increased and decreased, connectivity detection, and a settings page.

• The tutorial covers updating dependencies using the Pubspec assist extension, addressing errors, migrating to the custom BlocObserver class, and implementing HydratedBlocObserver for local data storage.