Flutter蓝牙通信插件flutter_blue_plus_windows的使用

Flutter蓝牙通信插件flutter_blue_plus_windows的使用

该项目是一个包装库，用于Flutter Blue Plus和Win_ble。它允许Flutter_blue_plus在Windows上运行。

通过最小的努力，你可以在Windows上使用Flutter Blue Plus。

使用方法

你只需要更改导入语句。

// 而不是 import 'package:flutter_blue_plus/flutter_blue_plus.dart';
import 'package:flutter_blue_plus_windows/flutter_blue_plus_windows.dart';

// 或者，当你导入FBP语句时可以隐藏FlutterBluePlus
import 'package:flutter_blue_plus/flutter_blue_plus.dart' hide FlutterBluePlus;
import 'package:flutter_blue_plus_windows/flutter_blue_plus_windows.dart';

扫描设备

final scannedDevices = <ScanResult>{};

const timeout = Duration(seconds: 3);
FlutterBluePlus.startScan(timeout: timeout);

final sub = FlutterBluePlus.scanResults.expand((e) => e).listen(scannedDevices.add);

await Future.delayed(timeout);
sub.cancel();
scannedDevices.forEach(print);

连接设备

final scannedDevice = scannedDevices
    .where((scanResult) => scanResult.device.platformName == DEVICE_NAME)
    .firstOrNull;
final device = scannedDevice?.device;
device?.connect();

断开设备连接

device?.disconnect();

查看Flutter Blue Plus的使用说明，请访问Flutter Blue Plus

示例代码

以下是一个完整的示例代码，展示了如何使用flutter_blue_plus_windows插件来扫描和连接蓝牙设备。

// Copyright 2017-2023, Charles Weinberger & Paul DeMarco.
// All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:async';

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

import 'screens/bluetooth_off_screen.dart';
import 'screens/scan_screen.dart';

void main() {
  FlutterBluePlus.setLogLevel(LogLevel.verbose, color: true);
  runApp(const FlutterBlueApp());
}

// 这个widget根据适配器状态显示BluetoothOffScreen或ScanScreen
class FlutterBlueApp extends StatefulWidget {
  const FlutterBlueApp({Key? key}) : super(key: key);

  [@override](/user/override)
  State<FlutterBlueApp> createState() => _FlutterBlueAppState();
}

class _FlutterBlueAppState extends State<FlutterBlueApp> {
  BluetoothAdapterState _adapterState = BluetoothAdapterState.unknown;

  late StreamSubscription<BluetoothAdapterState> _adapterStateStateSubscription;

  [@override](/user/override)
  void initState() {
    super.initState();
    _adapterStateStateSubscription = FlutterBluePlus.adapterState.listen((state) {
      _adapterState = state;
      if (mounted) {
        setState(() {});
      }
    });
  }

  [@override](/user/override)
  void dispose() {
    _adapterStateStateSubscription.cancel();
    super.dispose();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    Widget screen = _adapterState == BluetoothAdapterState.on
        ? const ScanScreen()
        : BluetoothOffScreen(adapterState: _adapterState);

    return MaterialApp(
      color: Colors.lightBlue,
      home: screen,
      navigatorObservers: [BluetoothAdapterStateObserver()],
    );
  }
}

// 这个观察者监听蓝牙关闭并弹出当前路由
class BluetoothAdapterStateObserver extends NavigatorObserver {
  StreamSubscription<BluetoothAdapterState>? _adapterStateSubscription;

  [@override](/user/override)
  void didPush(Route route, Route? previousRoute) {
    super.didPush(route, previousRoute);
    if (route.settings.name == '/DeviceScreen') {
      // 开始监听蓝牙状态变化当一个新的路由被推入时
      _adapterStateSubscription ??= FlutterBluePlus.adapterState.listen((state) {
        if (state != BluetoothAdapterState.on) {
          // 如果蓝牙关闭，则弹出当前路由
          navigator?.pop();
        }
      });
    }
  }

  [@override](/user/override)
  void didPop(Route route, Route? previousRoute) {
    super.didPop(route, previousRoute);
    // 当路由被弹出时取消订阅
    _adapterStateSubscription?.cancel();
    _adapterStateSubscription = null;
  }
}