Mixing native code with Flutter

Development
C, FFI, Flutter, Rust

Flutter is an open-source UI toolkit to build high-performance, high-fidelity, apps for iOS, Android, web, and desktop platforms. Flutter is written in Dart and provides developers with a rich set of widgets and tools to build beautiful and functional user interfaces. However, sometimes developers need to interact with existing code written in other languages. This is where Flutter’s FFI (Foreign Function Interface) comes into play.

The Flutter FFI is a powerful tool that allows developers to interact with native code written in languages such as C, C++, or Rust. The FFI provides a bridge between Flutter’s Dart code and native code, allowing the two to communicate with each other. This is incredibly useful for developers who need to integrate existing native code libraries into their Flutter apps or want to leverage the performance advantages of low-level languages.

Here are some of the benefits of using the Flutter FFI:

Access to Native Libraries

FFI allows developers to leverage existing native code libraries, which can be incredibly useful for certain types of apps. For example, if a developer needs to scan adapters on desktop, use a specific encryption algorithm, or monitor low level processes, they can use FFI to interact with a pre-existing native library that already handles these tasks. This can save time and resources, as the developer doesn’t have to reinvent the wheel.

Improved Performance

By using native code, developers can take advantage of the performance improvements that come with low-level languages like C and C++. For example, if a developer needs to do some heavy-duty number crunching or perform other compute-intensive tasks, using native code can result in significant performance improvements over doing the same tasks in Dart.

Simplified Porting of Existing Code

FFI can make it easier to port existing native code to Flutter, as it allows the two to communicate with each other. This means that developers can reuse their existing codebase, which can save time and effort.

Access to Platform-Specific Features

FFI allows developers to access platform-specific features that are not available in Flutter’s core API. For example, if a developer needs to interact with a specific feature on Windows, Mac or Linux they can use FFI to access that feature.

Access to Low-Level System Functions

Low-level system functions that are not available in the core Dart API can be accessed through the FFI. This can be incredibly useful for developers who need to interact with the underlying operating system, such as accessing files or interacting with system-level processes.

The future of Flutter and FFI

Whereas currently (early 2023) a wrapper is needed to interface between your native code and the Dart layer, in future releases of Dart this will become obsolete. Then it will become possible to call native code directly from Dart.

Conclusion

In conclusion, Flutter FFI is a powerful tool that can provide developers with a wide range of benefits. By allowing developers to interact with native code, the FFI provides access to existing libraries, improves performance, simplifies porting of existing code, provides access to platform-specific features, and gives access to low-level system functions. The FFI can be a powerful addition to any Flutter developer’s toolkit, and can help them create robust, performant, and functional apps.