README.md

flutter_package_import

A Flutter app which imports a package, wrapping a python module.

This example is intended to show how to import a Flutter package which internally uses the Dart Python FFi.

Table of Contents

Usage (the final product)

$ flutter run

This will launch the standard Flutter demo app. This app will display a counter and a button to increment the counter. Only difference is that to increment the counter, we use the flutter_package_export package. This package uses the Dart Python FFi to wrap a Python module, which is then used to increment the counter.

However, we do not need to know that the counter is incremented using a Python module. We only need import the flutter_package_export package and use it as any other Dart package.

Prerequisites

• None other than the standard Flutter prerequisites.

Adding the flutter_package_export package to the Flutter project

1. List the flutter_package_export package as a dependency in pubspec.yaml

# pubspec.yaml

dependencies:
  flutter:
    sdk: flutter
  flutter_package_export:
    path: ../flutter_package_export

2. Run flutter pub get

The following command should be run from the root of your Flutter project. It will install the flutter_package_export package.

$ flutter pub get

3. Import the flutter_package_export package

We then modify the lib/main.dart file to import the flutter_package_export package and use it to increment the counter.

// lib/main.dart

import "package:flutter/foundation.dart";
import "package:flutter/material.dart";
import 'package:flutter_package_export/flutter_package_export.dart';

Future<void> main() async {
  await initialize();
  runApp(const MyApp());
}

// ...

class _MyHomePageState extends State<MyHomePage> {
  // ...

  void _incrementCounter() {
    final int newCounter = add(_counter, 1).toInt();
    setState(() {
      _counter = newCounter;
    });
  }

// ...
}

Note the only three modifications:

1. Importing the flutter_package_export package.
2. Calling the initialize function in out main function.
3. Using the add function to increment the counter in the _incrementCounter function.

Next Step

Converting all supported types between Dart and Python. See the python_ffi_dart example.

Importing multiple Python modules in a Flutter app. See the python_ffi example.