Why Architecture Matters in Flutter Development?

Introduction

Just think of building a skyscraper without blueprints—wouldn't that sound chaotic? Architecture in software development serves as a blueprint, ensuring one can build the application with characteristics like robustness, scalability, and maintainability. When using Flutter, an ideal framework for constructing natively compiled apps in mobile, web, and desktop applications, architectural considerations become quite instrumental.

As businesses race to deliver feature-rich applications with faster development cycles, Flutter has gained immense popularity due to its ability to create beautiful, high-performance apps from a single codebase. However, with its flexibility comes a challenge: maintaining code quality and scalability as applications grow. This is where architecture plays a pivotal role, ensuring clean separation of concerns, improved testing capabilities, and long-term maintainability.

In this blog, we’ll explore why architecture is more than just a technical term in Flutter—it’s the foundation of successful app development. From understanding its core principles to learning how it impacts your project’s lifecycle, this guide will illuminate how investing in good architecture can elevate your Flutter projects to new heights.

History and Evolution of Architecture in Flutter

Origins: The Birth of Flutter and Early Challenges

Flutter is a UI toolkit developed by Google for natively compiled applications. It was first introduced in 2018 with the goal of alleviating the pain that developers were facing while trying to build cross-platform applications.Traditionally, most developers used frameworks like React Native or Xamarin to do this. The tools did support cross-platform abilities but suffered performance bottlenecks, had a lack of native support, and offered poor UX across different platforms.

Flutter overcame these issues with its "write once, run anywhere" philosophy, which used a single codebase to develop applications for iOS, Android, web, and desktop. The architecture of the framework was built around the Dart programming language, which enabled ahead-of-time (AOT) and just-in-time (JIT) compilation for high-performance apps. Flutter also introduced the concept of widgets for UI design, providing a seamless and consistent look across platforms.

This flexibility, however, brought along with it the complexity of growing application complexity. To maintain scalability, testability, and separation of concerns, especially in larger apps, Flutter developers required effective architectural patterns.

Evolution Over Time: Adapting to Modern Needs

1. Widget-Centric Development and MVC Inspiration (2018)

‍Early Flutter apps were widget-centric. Developers used widgets for both UI and state management. Although this was a good approach for small-scale applications, it quickly became unscalable. Flutter's widget tree resembled the classic MVC (Model-View-Controller) architecture, where:

• Model: Managed the application's data and business logic.
• View: Presented the UI, made up of Flutter widgets.
• Controller: Served as the intermediary, often used in StatefulWidgets.

2. State Management Solutions Emerge (2019)

‍As Flutter became popular, there was a requirement for better state management. Pattern like Provider was so widely adopted due to inspiration taken from MVVM (Model-View-ViewModel). In the MVVM structure:

• Model: This has encapsulated data of the application and business rules.
• View: Display the data; it will actually delegate user interactions towards the ViewModel.
• ViewModel: Responsible for managing state and logic that are related to UI, thereby bridging the Model and View.

Provider simplified state management by separating concerns, making it easier to scale applications while keeping the UI reactive.

3. BLoC (Business Logic Component) Architecture (2020)

The introduction of BLoC  brought a robust, reactive approach to Flutter. BLoC follows the stream-based model where:

• Events are dispatched to the BLoC.
• The BLoC processes these events and emits states.
• Widgets rebuild themselves by listening to these states.

This pattern offered a clean separation of UI and business logic, making apps more testable and scalable. It became a go-to solution for developers building medium to large-scale applications.

4. Clean Architecture and Modularity (2021-Present)

‍As complexity increased, Clean Architecture managed to serve their scalability problems. Inspired by Robert C. Martin’s principles, Clean Architecture in Flutter organizes codes into layers:

• Presentation. This primarily deals with the UI of an application, which includes widget and state management.
• Domain. This layer deals with business rules and use cases.
• Data: API calls, repositories, data sourcesThere are a set of modular implementations in the above description, which keep every layer as independent as possible, thereby reusing, testing, and maintaining better code.

5. Modern Tool Integration

‍Over time, Flutter was integrated with tools like Riverpod, GetX, and Cubit, each offering unique solutions for state management and architectural patterns. This helped developers to pick the most suitable architecture for their application's needs.

Problem Statement

In an application developed using Flutter, the code structure and organization become unwieldy with large applications. The lack of a clear architectural pattern leads to problems such as tight coupling, duplication, and the inability to handle state. This may lead to a monolithic code base where UI, business logic, and data management are intertwined, impossible to debug and scale.

Each architectural pattern—whether it is MVC, MVP, MVVM, BLoC, or Clean Architecture—tries to solve these problems using structured approaches of code organization. For example:

• MVC Model-View-Controller separates the concerns but lacks scalability as it causes the controller to grow uncontrollably in bigger applications.
• MVP Model-View-Presenter resolves some problems by delegating more work to the presenter, but then this also often results in a bloated presenter.
• MVVM focuses on reactive programming and binds UI elements directly to data, which simplifies the updates of the UI but requires a steep learning curve for developers who are not familiar with state management tools.
• BLoC introduces a reactive, stream-based approach, making state management predictable and scalable but requires a robust understanding of streams and reactive programming.
• Clean Architecture is modular and layered in its approach but separates UI, business logic, and data; it requires much more upfront planning and complexity for smaller applications.
• If an application does not adapt to an appropriate architectural pattern, then it runs the risk of technical debt, becomes harder to scale, and ultimately fails to meet user expectations.

Technology Overview

Flutter works by building a tree of widgets that describe the UI and the behavior of that UI. The different types of widgets are either stateless-unchanging-or stateful-dynamic and interactive. Developers do all this in terms of how the application appears and behaves by composing widgets hierarchically into a widget tree.

Example a button that changes a counter when pressed can be represented as

• A StatelessWidget for the appearance of the button.
• A StatefulWidget to track counter's value and fire rebuilds.

Whenever the counter is updated, Flutter 'smartly' rebuilds only the components of the UI that depend on this change. This feature of reactive rendering facilitates smooth and responsive application.There are some architectural patterns for large-scale applications:MVC (Model-View-Controller): The View (UI) of an application is separated from Model (business logic) using a Controller to act as an intermediary between them.MVVM (Model-View-ViewModel): It binds the View to the ViewModel for two-way data flow, ensuring a reactive UI.BLoC (Business Logic Component): Streams are used to manage state and business logic in a predictable, scalable manner.Clean Architecture: The application is divided into layers, namely Presentation, Domain, and Data, for maintainability and testability.Flutter also supports powerful state management tools like Provider, GetX, and Riverpod, which simplify handling user interactions, API calls, and application state.

Challenges and Limitations

Current Challenges

1. Choice Overload:

Flutter provides no default architectural pattern, leaving developers with a wide range of options such as MVC, MVP, MVVM, BLoC, and Clean Architecture. This freedom can be overwhelming, especially for beginners, leading to inconsistent implementations across teams.

2. Complexity in State Management:

Managing state in Flutter apps can be challenging as the application scales. Developers must choose from numerous state management solutions (Provider, Riverpod, GetX, BLoC), each with its own learning curve and trade-offs.

3. Scalability Issues:

Without proper planning, some architectures like MVC or widget-centric designs can lead to tightly coupled codebases. This makes scaling and maintaining large applications difficult.

4. Performance Overhead:

Complex architectural patterns, such as Clean Architecture, may introduce additional layers and boilerplate code, potentially affecting development speed and runtime performance for smaller applications.

Potential Solutions

1. Standardization: Teams can adopt community-recommended architectural guidelines, such as BLoC or Clean Architecture, tailored to the size and complexity of their projects. Flutter’s documentation and best practices are improving to help developers make informed choices.
2. Simplified State Management: Tools like GetX and Riverpod offer more intuitive approaches to state management, reducing boilerplate and complexity.
3. Modular Design: Following modular design principles ensures that the codebase remains maintainable and scalable, regardless of the architecture chosen.

Future Outlook

As Flutter continues to evolve, its architectural landscape is poised for significant advancements. With the growing adoption of Flutter for cross-platform development, there is an increasing emphasis on streamlining best practices for architecture. Developers are expected to see more community-driven guidelines and official recommendations to simplify decision-making around architectural patterns.

State management solutions are also evolving to become more intuitive and efficient. Emerging tools like Riverpod and improvements in GetX aim to minimize boilerplate code while enhancing scalability and maintainability. Additionally, the integration of Flutter with emerging technologies like machine learning, augmented reality, and IoT will require more robust architectural patterns to handle complex workflows.

Another key trend is the push toward modularity and reusability. Architectures like Clean Architecture are becoming increasingly popular for their ability to support larger, more scalable applications. Coupled with the anticipated improvements in Flutter’s performance and tooling, developers will have access to more efficient ways to manage application complexity.

Overall, the future of architecture in Flutter promises a more standardized, efficient, and developer-friendly ecosystem, empowering teams to build high-quality, maintainable applications that cater to diverse platforms and industries.

Conclusion

In this blog, we explored the importance of architecture in Flutter development, discussing various architectural patterns like MVC, MVP, MVVM, BLoC, and Clean Architecture. Each pattern addresses specific challenges related to code organization, state management, and scalability. We highlighted the current challenges, such as state complexity and performance overhead, and offered insights into potential solutions, like adopting tools like GetX and Riverpod, and following modular design principles.

As Flutter continues to evolve, the future of architecture in Flutter looks promising, with more streamlined best practices, improved state management tools, and a focus on scalability and maintainability. By understanding these architectural approaches, developers can build more efficient, robust, and user-friendly applications across multiple platforms.