s2_sdk_dart #

A new Dart FFI package project.

Getting Started #

This project is a starting point for a Flutter FFI package, a specialized package that includes native code directly invoked with Dart FFI.

Project structure #

This template uses the following structure:

• src: Contains the native source code, and a CmakeFile.txt file for building that source code into a dynamic library.

• lib: Contains the Dart code that defines the API of the plugin, and which calls into the native code using dart:ffi.

• bin: Contains the build.dart that performs the external native builds.

Building and bundling native code #

build.dart does the building of native components.

Bundling is done by Flutter based on the output from build.dart.

Binding to native code #

To use the native code, bindings in Dart are needed. To avoid writing these by hand, they are generated from the header file (src/s2_sdk_dart.h) by package:ffigen. Regenerate the bindings by running dart run ffigen --config ffigen.yaml.

Invoking native code #

Very short-running native functions can be directly invoked from any isolate. For example, see sum in lib/s2_sdk_dart.dart.

Longer-running functions should be invoked on a helper isolate to avoid dropping frames in Flutter applications. For example, see sumAsync in lib/s2_sdk_dart.dart.

Flutter help #

For help getting started with Flutter, view our online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.