flutter_web_bluetooth 0.2.4

A library to use the web bluetooth api in your web project. Will play nice if used in IO projects.

example/lib/main.dart

import "dart:async";

import "package:flutter/material.dart";
import "package:flutter_web_bluetooth/flutter_web_bluetooth.dart";
import "package:flutter_web_bluetooth_example/business/bluetooth_business.dart";
import "package:flutter_web_bluetooth_example/model/main_page_device.dart";
import "package:flutter_web_bluetooth_example/pages/device_services_page.dart";
import "package:flutter_web_bluetooth_example/web_helpers/web_helpers.dart";
import "package:flutter_web_bluetooth_example/widgets/bluetooth_device_widget.dart";
import "package:flutter_web_bluetooth_example/widgets/floating_action_buttons.dart";
import "package:flutter_web_bluetooth_example/widgets/info_dialog.dart";

const redirect = bool.fromEnvironment("redirectToHttps", defaultValue: false);

void main() {
  if (redirect) {
    WebHelpers.redirectToHttps();
  }
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(final BuildContext context) {
    return StreamBuilder<bool>(
      stream: FlutterWebBluetooth.instance.isAvailable,
      initialData: false,
      builder:
          (final BuildContext context, final AsyncSnapshot<bool> snapshot) {
        final available = snapshot.requireData;
        return MaterialApp(
            home: Scaffold(
          appBar: AppBar(
              title: const SelectableText("Bluetooth web example app"),
              actions: [
                Builder(builder: (final BuildContext context) {
                  return IconButton(
                      onPressed: () async {
                        await InfoDialog.showInfoDialog(context);
                      },
                      icon: const Icon(Icons.info));
                }),
              ]),
          body: MainPage(
            isBluetoothAvailable: available,
          ),
          floatingActionButtonLocation: FloatingActionButtonLocation.endDocked,
          floatingActionButton: const FABS(),
        ));
      },
    );
  }
}

class MainPage extends StatefulWidget {
  final bool isBluetoothAvailable;

  const MainPage({
    required this.isBluetoothAvailable,
    super.key,
  });

  @override
  State<StatefulWidget> createState() {
    return MainPageState();
  }
}

class MainPageState extends State<MainPage> {
  Stream<Set<MainPageDevice>>? _devicesStream;

  Color? _getErrorColor() {
    if (!mounted) {
      return null;
    }
    final theme = Theme.of(context);
    return theme.colorScheme.error;
  }

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

    _devicesStream = BluetoothBusiness.createDeviceStream();
  }

  Future<void> handleDeviceTap(final MainPageDevice device) async {
    DeviceServicesPage? page;
    if (device is MainPageDevice<BluetoothDevice>) {
      page = DeviceServicesPage(bluetoothDevice: device.device);
    } else {
      final state =
          await BluetoothBusiness.requestAdvertisementDevice(device.device);

      late String message;
      switch (state.state) {
        case RequestDeviceState.adapterNotAvailable:
          message = "No bluetooth adapter available";
          break;
        case RequestDeviceState.userCancelled:
          message = "User canceled the dialog";
          break;
        case RequestDeviceState.deviceNotFound:
          message = "No devices found";
          break;
        case RequestDeviceState.ok:
          message = "";
          break;
        case RequestDeviceState.other:
        default:
          message = "Unknown error";
          break;
      }

      if (state.state == RequestDeviceState.ok && state.device == null) {
        message = "Unknown error";
      }

      if (message.isNotEmpty && mounted) {
        ScaffoldMessenger.maybeOf(context)?.showSnackBar(SnackBar(
          content: Text(message),
          backgroundColor: _getErrorColor(),
        ));
      } else {
        page = DeviceServicesPage(bluetoothDevice: state.device!);
      }
    }

    if (page != null && mounted) {
      final finalPage = page;
      Navigator.push(context,
          MaterialPageRoute(builder: (final BuildContext context) {
        return finalPage;
      }));
    } else {
      debugPrint("Could not open the page because not mounted anymore");
    }
  }

  @override
  Widget build(final BuildContext context) {
    return Column(children: [
      MainPageHeader(
        isBluetoothAvailable: widget.isBluetoothAvailable,
      ),
      const Divider(),
      Expanded(
        child: StreamBuilder(
          stream: _devicesStream,
          initialData: const {},
          builder: (final BuildContext context, final AsyncSnapshot snapshot) {
            final devices = snapshot.requireData;
            return ListView.builder(
              itemCount: devices.length,
              itemBuilder: (final BuildContext context, final int index) {
                final device = devices.toList()[index];

                return BluetoothDeviceWidget(
                  bluetoothDevice: device,
                  onTap: () async {
                    await handleDeviceTap(device);
                  },
                );
              },
            );
          },
        ),
      ),
    ]);
  }
}

class MainPageHeader extends StatelessWidget {
  const MainPageHeader({required this.isBluetoothAvailable, super.key});

  final bool isBluetoothAvailable;

  @override
  Widget build(final BuildContext context) {
    final text = isBluetoothAvailable ? "supported" : "unsupported";

    final screenWidth = MediaQuery.of(context).size.width;
    final phoneSize = screenWidth <= 620.0;

    final children = <Widget>[
      SizedBox(
          width: phoneSize ? screenWidth : screenWidth * 0.5,
          child: ListTile(
            title: const SelectableText("Bluetooth api available"),
            subtitle: SelectableText(
                FlutterWebBluetooth.instance.isBluetoothApiSupported
                    ? "true"
                    : "false"),
          )),
      SizedBox(
          width: phoneSize ? screenWidth : screenWidth * 0.5,
          child: ListTile(
            title: const SelectableText("Bluetooth available"),
            subtitle: SelectableText(text),
          )),
    ];

    if (phoneSize) {
      children.insert(1, const Divider());
      return Column(
        children: children,
      );
    } else {
      return Row(children: children);
    }
  }
}