Some examples of using FFI, as presented at the Flutter Vikings conference in August 2022.
A very basic example of using FFI. The mathlib subfolder contains
mathlib.cpp, which offers a function that adds two integers. calc.dart calls
the resultant DLL with Dart FFI.
An example of how to set 'raw mode', used for full-screen console applications.
Raw mode disables console echo, switches from line input to character input, and
disables processing of control codes like Ctrl+C, among other things. The
rawmode_c subfolder shows the C code to enable / disable raw mode in
macOS/Linux and Windows using system APIs.
The stdin_raw.dart file shows an example extension method that uses Dart FFI
to turn rawmode on or off. The sample is deliberately simple for tutorial
purposes (e.g. it does not provide a getter, nor does it test the existing flags
before setting them).
rawtest.dart shows an example of using this. Try running the Dart sample and
then press Ctrl+C after each prompt.
getrawmode.dart demonstrates allocating memory on the native heap, as is
necessary for working with pointers.
Shows a full-screen text editor built in Dart, based on kilo.c. This uses
dart_console, a multiplatform Dart
package for manipulating the console that is built on the techniques
demonstrated above.
Demonstrates a simple example of calling a Win32 API from Dart. This uses
win32, a package that wraps many Windows
APIs for ease of calling from Dart code.
An example of calling a COM-based Win32 API. This example instantiates the COM
runtime, and then opens the File / Open common dialog box. The results are
returned as a separate COM interface (IShellItem), which is interrogated for
the filename.
An example of using the winmd package to
catalog Win32 APIs. This uses the Microsoft
win32metadata repository, which
provides a database of traditional (Win32/COM) API metadata.
Demonstrates a Flutter app that uses a Dart embedder, rather than the supplied
C++ embedder. Run compile.cmd to build it on a machine with the Flutter SDK
installed (no Visual Studio is required, since no C++ compilation takes place).