flutter_blue和后台服务:MissingPluginException在通道上没有找到实现

Question

我想让蓝牙工作(连接到设备)在后台。但我得到以下错误:

E/flutter (15225): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: MissingPluginException(No implementation found for method isAvailable on channel plugins.pauldemarco.com/flutter_blue/methods)
E/flutter (15225): #0      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:156:7)
E/flutter (15225): <asynchronous suspension>
E/flutter (15225): #1      FlutterBlue._setLogLevelIfAvailable (package:flutter_blue/src/flutter_blue.dart:77:9)
E/flutter (15225): <asynchronous suspension>

重现这个问题很简单:

1. 创建一个Flutter应用程序

2. 添加以下包:

   flutter pub add flutter_blue

   flutter pub add flutter_background_service

然后启动后台服务并触发它

void main() {
WidgetsFlutterBinding.ensureInitialized();
FlutterBackgroundService.initialize(onStart);
runApp(MyApp());
}
void onStart() {
WidgetsFlutterBinding.ensureInitialized();
final service = FlutterBackgroundService();
service.onDataReceived.listen((event) {
if (event!["bluetooth"] == "start") {
FlutterBlue flutterBlue = FlutterBlue.instance;
flutterBlue.startScan(timeout: Duration(seconds: 4));

var subscription = flutterBlue.scanResults.listen((results) {
for (ScanResult r in results) {
print('${r.device.name} found! rssi: ${r.rssi}');
}
});

flutterBlue.stopScan();
return;
}

});

service.setForegroundMode(false);
}

IconButton(
onPressed: (){
FlutterBackgroundService().sendData({"bluetooth": "start"},);
},
icon: Icon(Icons.bluetooth),
)

提前感谢您的帮助

Answer 1

使用最新的FlutterBluePlus插件…

它几乎是一个直接的替代品:你所要做的就是用FlutterBluePlus替换代码中的FlutterBlue…