mirror of https://github.com/flutter/samples.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
94 lines
3.1 KiB
94 lines
3.1 KiB
# FFIgen + JNIgen pedometer
|
|
|
|
This is a demo for some of our tooling around
|
|
calling platform APIs directly from dart code.
|
|
This repository represents a demo of a plugin that leverages FFIgen & JNIgen.
|
|
There is also an example pedometer app that
|
|
uses the bindings generated from these tools.
|
|
|
|
- [FFIgen](https://pub.dev/packages/ffigen) is used to generate
|
|
bindings for C, Objective-C and Swift APIs.
|
|
- [JNIgen](https://pub.dev/packages/jnigen) is used to generate
|
|
bindings for Java and Kotlin APIs.
|
|
|
|
**These tools are both experimental and are currently a work in progress.**
|
|
If you find any issues or have feedback,
|
|
please file it on the corresponding GitHub repositories.
|
|
|
|
## Re-generating bindings
|
|
|
|
The bindings that allow the Dart code to call the platform code have
|
|
already been generated in the [`\lib` folder](./lib).
|
|
You can regenerate them by following the steps below:
|
|
|
|
### FFIgen
|
|
|
|
Configuration of FFIgen for the
|
|
[CoreMotion framework](https://developer.apple.com/documentation/coremotion)
|
|
is in the [`ffigen.yaml` file](./ffigen.yaml).
|
|
FFIgen currently does not support autogenerating code to handle callbacks.
|
|
So, there are a few extra steps needed to
|
|
appropriately handle callbacks in Objective-C.
|
|
You can read more about this limitation on
|
|
[dart.dev](https://dart.dev/interop/objective-c-interop#callbacks-and-multithreading-limitations).
|
|
|
|
```bash
|
|
dart run ffigen --config ffigen.yaml
|
|
```
|
|
|
|
|
|
### JNIgen
|
|
|
|
Configuration of JNIgen for the
|
|
[HealthConnect API](https://developer.android.com/guide/health-and-fitness/health-connect)
|
|
is in the [`jnigen.yaml` file](./jnigen.yaml).
|
|
|
|
1. Build an Android APK file from the example app.
|
|
Currently, JNIgen requires at least one APK build
|
|
to obtain the classpaths of Android Gradle libraries.
|
|
|
|
```bash
|
|
cd example && flutter build apk
|
|
```
|
|
|
|
2. Return to the `/pedometer` directory and run `jnigen`:
|
|
|
|
```bash
|
|
cd .. && dart run jnigen --config jnigen.yaml
|
|
```
|
|
|
|
## Running the example app
|
|
|
|
The example app is located in the [`/example`](./example) directory,
|
|
and the following commands assume they are being run from that location.
|
|
|
|
Note that step counting is only available on physical devices.
|
|
|
|
### iOS
|
|
|
|
- Run `flutter run` and choose your physical device.
|
|
- Allow the *pedometer* app access to step counting.
|
|
|
|
### Android
|
|
|
|
- Make sure that [Google Fit](https://play.google.com/store/apps/details?id=com.google.android.apps.fitness)
|
|
is installed (to ensure that steps are being counted).
|
|
- Run `flutter run` and choose your physical device.
|
|
- Install [Health Connect](https://play.google.com/store/apps/details?id=com.google.android.apps.healthdata)
|
|
and grant access to Google Fit and the *jni_demo* app.
|
|
|
|
|
|
## Project structure
|
|
|
|
* `src`: Contains the native source code, and a `CMakeLists.txt` file for
|
|
building that source code into a dynamic library.
|
|
|
|
* `lib`: Contains the Dart code that defines the API of the plugin and
|
|
calls into the native code using `dart:ffi`.
|
|
|
|
* platform folders (`ios` etc.): Contain the build files for
|
|
building and bundling the native code library with the platform application.
|
|
|
|
* `example`: Contains the native source code for building
|
|
that source code into a dynamic library.
|