Bloc provided toBlocProvider with get_it vs direct instantiation: A Comprehensive Guide

In the world of Flutter, Blocs and Providers are two popular architectural patterns used to manage app state and inject dependencies. When it comes to providing a Bloc to a BlocProvider, developers often wonder whether to use get_it or direct instantiation. In this article, we’ll dive into the differences between these two approaches, exploring the pros and cons of each, and provide a clear guide on how to implement them.

What is get_it?

get_it is a popular Flutter package for service location and dependency injection. It provides a simple and efficient way to register and retrieve instances of your app’s services, including Blocs. get_it is often used to decouple dependencies between widgets and services, making it easier to test and maintain your app.

How to use get_it with BlocProvider

To use get_it with BlocProvider, you need to register your Bloc instance with get_it and then retrieve it in your BlocProvider. Here’s an example:

// Register Bloc instance with get_it
GetIt getIt = GetIt.instance;
getIt.registerSingleton<MyBloc>(MyBloc());

// Use BlocProvider with get_it
MultiBlocProvider(
  providers: [
    BlocProvider<MyBloc>(
      create: (_) => getIt<MyBloc>(),
    ),
  ],
  child: MyApp(),
)

Direct Instantiation

Direct instantiation involves creating an instance of your Bloc directly in your BlocProvider. This approach is straightforward and easy to implement, but it has its own set of limitations.

How to use direct instantiation with BlocProvider

To use direct instantiation with BlocProvider, you simply create an instance of your Bloc and pass it to the BlocProvider:

// Use BlocProvider with direct instantiation
MultiBlocProvider(
  providers: [
    BlocProvider<MyBloc>(
      create: (_) => MyBloc(),
    ),
  ],
  child: MyApp(),
)

Pros and Cons of each approach

In this section, we’ll discuss the advantages and disadvantages of using get_it and direct instantiation with BlocProvider.

get_it approach

Pros	Cons
Decouples dependencies between widgets and services Allows for easy testing and mocking of services Provides a single point of truth for service instances	Requires additional package dependency (get_it) Can add complexity to your app’s architecture

Direct Instantiation approach

Pros	Cons
Simpler to implement and understand No additional package dependencies required Faster development and prototyping	Tightly couples dependencies between widgets and services Makes testing and mocking more difficult

When to use each approach

In this section, we’ll provide guidance on when to use get_it and when to use direct instantiation with BlocProvider.

Use get_it when:

• You need to decouple dependencies between widgets and services
• You want to make testing and mocking easier
• You have a large, complex app with multiple services and dependencies

Use direct instantiation when:

• You’re building a small to medium-sized app with simple dependencies
• You want to minimize package dependencies and complexity
• You’re in the early stages of development and prototyping

Best Practices and Conclusion

In conclusion, both get_it and direct instantiation are viable options for providing a Bloc to a BlocProvider. However, it’s essential to consider the pros and cons of each approach and choose the one that best fits your app’s needs.

Here are some best practices to keep in mind:

1. Use get_it for complex apps with multiple services and dependencies
2. Use direct instantiation for small to medium-sized apps with simple dependencies
3. Decouple dependencies between widgets and services whenever possible
4. Test and mock your services to ensure they’re working as expected

By following these guidelines and understanding the differences between get_it and direct instantiation, you’ll be able to make an informed decision and build a robust, maintainable Flutter app.

Remember, the key to success lies in choosing the right approach for your specific use case and app requirements. Happy coding!

Frequently Asked Question

Get ready to dive into the world of Bloc and Provider, where dependency injection is the name of the game!