如何在后台使用flutter_blue扫描并连接BLE设备

import 'package:flutter_blue/flutter_blue.dart';

FlutterBlue flutterBlue = FlutterBlue.instance;

flutterBlue.startScan(timeout: Duration(seconds: 4));

flutterBlue.scanResults.listen((results) {
  // 处理扫描结果
  for (ScanResult r in results) {
    print('${r.device.name} found! rssi: ${r.rssi}');
  }
});

flutterBlue.stopScan();

flutterBlue.connect(device).then((value) {
  // 连接成功，可以进行数据交互
}).catchError((error) {
  // 连接失败，处理错误
});

device.state.listen((state) {
  if (state == BluetoothDeviceState.connected) {
    // 设备已连接
  } else if (state == BluetoothDeviceState.disconnected) {
    // 设备已断开连接
  }
});

characteristic.read().then((value) {
  // 读取到的数据
}).catchError((error) {
  // 读取失败，处理错误
});

characteristic.write(data).then((value) {
  // 写入成功
}).catchError((error) {
  // 写入失败，处理错误
});