flutter_gpiod 0.1.0+3

Flutter package for accessing libgpiod on linux. Supports signal edge listening, active state, open source/drain and (if supported by platform) bias. Only works with flutter-pi.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'dart:async';

import 'package:flutter_gpiod/flutter_gpiod.dart';

void main() => runApp(FlutterGpiodTestApp());

class FlutterGpiodTestApp extends StatefulWidget {
  @override
  _FlutterGpiodTestAppState createState() => _FlutterGpiodTestAppState();
}

class _FlutterGpiodTestAppState extends State<FlutterGpiodTestApp> {
  Future<void> _testFlutterGpiod() async {
    final gpio = await FlutterGpiod.getInstance();

    /// Retrieve the list of GPIO chips.
    final chips = gpio.chips;

    /// Print out all GPIO chips and all lines
    /// for all GPIO chips.
    for (var chip in chips) {
      print("$chip");

      for (var line in chip.lines) {
        print("  ${await line.info}");
      }
    }

    /// Retrieve the line with index 23 of the first chip.
    /// This is BCM pin 23 for the Raspberry Pi.
    ///
    /// I recommend finding the chip you want
    /// based on the chip label, as is done here.
    ///
    /// In this example, we search for the main Raspberry Pi GPIO chip,
    /// which has the label `pinctrl-bcm2835`, and then retrieve the line
    /// with index 23 of it. So [line] is GPIO pin BCM 23.
    final line =
        chips.singleWhere((chip) => chip.label == 'pinctrl-bcm2835').lines[23];

    /// Request BCM 23 as output.
    await line.requestOutput(
        consumer: "flutter_gpiod test", initialValue: true);

    /// Pulse the line.
    /// Set it to inactive. (so low voltage = GND)
    await line.setValue(false);
    await Future.delayed(Duration(milliseconds: 500));
    await line.setValue(true);
    await Future.delayed(Duration(milliseconds: 500));

    await line.release();

    /// Now we're listening for falling and rising edge events
    /// on BCM 23.
    await line.requestInput(
        consumer: "flutter_gpiod input test",
        triggers: {SignalEdge.falling, SignalEdge.rising});

    /// Log line events for eternity.
    await for (final event in line.onEvent) {
      print("flutter_gpiod line event: $event");
    }

    /// Release the line, though we'll never reach this point.
    await line.release();
  }

  @override
  void initState() {
    super.initState();
    _testFlutterGpiod();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
          appBar: AppBar(
            title: const Text('flutter_gpiod Test App'),
          ),
          body: Container()),
    );
  }
}