Flutter配件设置插件flutter_accessorysetup的使用

目前库支持的功能包括：

• ✅ BLE（低功耗蓝牙）
• ✅ WiFi
• ✅ 迁移

重要提示：根据Apple的设计，该库仅适用于 iOS 18及以上版本。

如何使用

通过命令行安装库：

flutter pub get flutter_accessorysetup

设置

详细信息可参考 Apple文档。

Info.plist配置

你需要在iOS应用的Info.plist文件中添加相应的键以使其正常工作。如果缺少必要的键，应用在显示选择器时会崩溃。

始终需要配置的键

<key>NSAccessorySetupKitSupports</key>
<array>
  <string>Bluetooth</string>
  <string>WiFi</string>
</array>

使用ASDiscoveryDescriptor配置bluetoothServiceUUID

<key>NSAccessorySetupBluetoothServices</key>
<array>
  <string>149E9E42-33AD-41AD-8665-70D153533EC1</string>
</array>

注意：这里的UUID字符串必须大写。

使用ASDiscoveryDescriptor配置bluetoothNameSubstring

<key>NSAccessorySetupBluetoothNames</key>
<array>
  <string>DeviceName</string>
</array>

注意：此功能在iOS 18开发者预览版2中无法使用。

其他制造商ID选项未在此处覆盖。

使用FlutterAccessorySetup类

参考完整的代码示例，可以在示例应用中查看。

final _accessorySetup = FlutterAccessorySetup();

void activate() {
  _accessorySetup.eventStream.listen((event) {
    debugPrint('Got event: ${event.eventType}');
    // 处理会话事件
  });
  await _accessorySetup.activate();
  try {
    _accessorySetup.showPickerForDevice(
      'My Ble', 
      Assets.images.ble.path, 
      '4013ABDE-11C0-49E7-9939-4B4567C26ADA'
    );
  } on PlatformException {
    debugPrint('Failed to show the picker');
  }
}

void deactivate() {
  _accessorySetup.dispose();
  super.deactivate();
}

我们知道什么

• 应用在使用选择器与蓝牙设备交互时，无需请求蓝牙权限。
• 用户从选择器中选择设备非常方便。
• 如果想在同一类型设备中显示多个设备，每个设备应广播一个唯一的名称。选择器只会显示每种唯一名称的一个设备。如果设备暴露了0x1800服务，则该服务中的设备名称也应唯一。
• 当用户点击关闭按钮退出选择器时，showPicker闭包将发出错误（ASErrorDomain, code 700）。请注意处理这种情况。
• 如果用户选择了一个BLE配件，选择器将发送一个类型为ASAccessoryEventType.accessoryChanged的事件。但据观察，选择器应发送ASAccessoryEventType.accessoryAdded类型的事件，这可能是一个bug。
• 如果设备之前已连接过，它会在会话激活后出现在session.accessories数组中。
• 如果设备已被其他应用连接过，选择器将显示由其他应用装饰过的设备——即图像和名称来自那个应用，而不是你提供的。要更改装饰，用户应该将设备添加到你的应用中。
• 当用户通过选择器选择设备时：
  • 设备将在移动应用设置中的Settings/Apps/YourApp下的Accessories部分显示。
  • 设备将在Settings/Bluetooth下的My Devices部分显示。
  • 设备的信息屏幕将显示在发现过程中提供的图像和名称（即用户在选择器中看到的内容）。
• 如果用户删除了应用，设备将自动断开连接。它将不再显示在Settings/Bluetooth屏幕的My Devices部分。

请注意：AccessorySetup在模拟器上不工作。

参考资料

• Discovering and Configuring Accessories
• Authorizing a Bluetooth Accessory to Share a Dice Roll

示例代码

以下是从示例应用中摘录的代码：

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

import 'package:flutter_accessorysetup/flutter_accessorysetup.dart';
import 'package:flutter_accessorysetup/gen/ios/accessory_setup_bindings.dart';
import 'package:flutter_accessorysetup_example/gen/assets.gen.dart';
import 'package:flutter_blue_plus/flutter_blue_plus.dart';

void main() {
  runApp(const MyApp());
}

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

  [@override](/user/override)
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _deviceStatus = 'Disconnected';
  String _events = "";
  ASAccessory? _pickedAccessory;
  StreamSubscription<BluetoothAdapterState>? _adapterStateSubscription;
  StreamSubscription<ASAccessoryEvent>? _eventsSubscription;
  final _accessorySetup = FlutterAccessorySetup();

  [@override](/user/override)
  void initState() {
    super.initState();
    _activateAccessorySession();
  }

  [@override](/user/override)
  void deactivate() {
    _adapterStateSubscription?.cancel();
    _eventsSubscription?.cancel();
    _accessorySetup.dispose();
    super.deactivate();
  }

  Future<void> _activateAccessorySession() async {
    _accessorySetup.eventStream.listen((event) {
      debugPrint('Got event: ${event.eventType}');
      setState(() {
        _events += '\n\r${event.dartDescription};\n\r';
      });
      if (event.eventType == ASAccessoryEventType.ASAccessoryEventTypeActivated) {
        connect();
      } else if (event.eventType == ASAccessoryEventType.ASAccessoryEventTypeAccessoryAdded || event.eventType == ASAccessoryEventType.ASAccessoryEventTypeAccessoryChanged) {
        setState(() {
          _pickedAccessory = event.accessory;
        });
      } else if (event.eventType == ASAccessoryEventType.ASAccessoryEventTypePickerDidDismiss) {
        debugPrint('user picked accessory: $_pickedAccessory)');
        final accessory = _pickedAccessory;
        setState(() {
          _pickedAccessory = null;
        });
        final id = accessory?.dartBluetoothIdentifier;
        if (accessory != null && id != null && accessory.state == ASAccessoryState.ASAccessoryStateAuthorized) {
          _connectWithoutScanning(id);
        } else {
          throw Exception('added accessory should have identifier and be authorized');
        }
      }
    });
    _accessorySetup.activate();
  }

  Future<void> connect() async {
    final firstAccessoryId = _accessorySetup.accessories.firstOrNull?.dartBluetoothIdentifier;
    if (firstAccessoryId != null) {
      debugPrint('Got an accessory, will try to connect: $firstAccessoryId');
      await _connectWithoutScanning(firstAccessoryId);
      return;
    }

    try {
      // 为了使其正常工作，需要设置info.plist键
      // NSAccessorySetupBluetoothServices -> UUID
      // 和 NSAccessorySetupKitSupports -> Bluetooth
      _accessorySetup.showPickerForDevice('My Ble', Assets.images.ble.path, '4013ABDE-11C0-49E7-9939-4B4567C26ADA');
    } catch (e) {
      if (e is NativeCodeError) {
        debugPrint('Got native code error: $e');
      } else {
        debugPrint('Got error: $e');
      }
    }
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Accessory Setup App'),
        ),
        body: Center(
          child: Column(
            children: [
              Text('Device Status: $_deviceStatus'),
              const SizedBox(height: 15),
              Text('Setup Session Events: \n$_events'),
            ],
          ),
        ),
      ),
    );
  }

  // 连接设备部分

  Future<void> _connectWithoutScanning(String id) async {
    debugPrint('_connectWithoutScanning: $id');
    if (await FlutterBluePlus.isSupported == false) {
      debugPrint('Bluetooth is not supported by this device');
      return;
    }
    if (FlutterBluePlus.adapterStateNow == BluetoothAdapterState.on) {
      _connectDevice(id);
      return;
    }
    _adapterStateSubscription = FlutterBluePlus.adapterState.listen((BluetoothAdapterState state) {
      debugPrint('got adapter state: $state');
      if (state == BluetoothAdapterState.on) {
        _connectDevice(id);
        _adapterStateSubscription?.cancel();
      }
    });
  }

  Future<void> _connectDevice(String id) async {
    var device = BluetoothDevice.fromId(id);
    debugPrint('loaded device: $device');
    try {
      await device.connect();
      setState(() {
        _deviceStatus = 'Connected';
      });
      debugPrint('connected to device $device');
    } catch (e) {
      debugPrint('failed to connect: $e');
    }
  }
}