'package:flutter/src/widgets/navigator.dart'：断言失败：第 4517 行 pos 12：'！_debugLocked'：不是真的

如何解决'package:flutter/src/widgets/navigator.dart'：断言失败：第 4517 行 pos 12：'！_debugLocked'：不是真的

我正在使用 BLE esp32 从传感器获取数据，但是当我想通过从 BLE 设备获取数据进行校准时，它在我在设备设置屏幕中使用的 Stream Builder 上出现此错误。我一按配置，它就会移动到设备设置页面。我想要的是，在我从 BLE 获得值 1 之前，它应该继续显示此屏幕

一旦 1 出现，它应该转到另一个屏幕显示一条消息和图片，然后在 2 秒后自动移动到主页。

但它显示底部溢出错误消息“蓝牙未激活”，我该如何避免？并跳转到下一页？ BLE 也处于活动状态，因为我检查了另一个屏幕上的值，但是对于连接的设备，此屏幕上没有发生这种情况。此外，设备完成页面甚至不会进入主屏幕 我是 Flutter 的新手，这就是为什么我不知道我应该用它做什么。

设备设置屏幕代码：

import 'dart:typed_data';

import 'package:epicare/confdeviceDone.dart';
import 'package:epicare/ConfigurationScreen.dart';
import 'package:Flutter/material.dart';
import 'package:Flutter_blue/Flutter_blue.dart';
import 'package:Flutter_spinkit/Flutter_spinkit.dart';
import 'package:Fluttertoast/Fluttertoast.dart';

import 'Homepage.dart';

class confdeviceSet extends StatefulWidget {
  const confdeviceSet({Key key,this.device}) : super(key: key);
  final BluetoothDevice device;
  @override
  _confdeviceSetState createState() => _confdeviceSetState();
}

class _confdeviceSetState extends State<confdeviceSet> {
  // BLE
  final String SERVICE_UUID = "4fafc201-1fb5-459e-8fcc-c5c9c331914b";
  //final String SERVICE_UUID = "0365a300-8d69-4066-80c7-554298a6ec5e";
  //final String CHaraCTERISTIC_UUID = "cf01c075-cb75-4dea-819e-2a79dd466bcb";
  final String CHaraCTERISTIC_UUID = "beb5483e-36e1-4688-b7f5-ea07361b26a8";
  bool isReady;
  Stream<List<int>> stream;
  List<int> lastValue;
  List<double> traceDust = List();
  @override
  void initState() {
    isReady = false;
    discoverServices();
  }

  discoverServices() async {
    List<BluetoothService> services = await widget.device.discoverServices();
    services.forEach((service) {
      if (service.uuid.toString() == SERVICE_UUID) {
        service.characteristics.forEach((characteristic) {
          if (characteristic.uuid.toString() == CHaraCTERISTIC_UUID) {
            characteristic.setNotifyValue(!characteristic.isnotifying);
            stream = characteristic.value;
            //print(stream);
            lastValue = characteristic.lastValue;
            //print(lastValue);

            setState(() {
              isReady = true;
            });
          }
        });
      }
    });
  }

  _dataParser(List<int> data) {
    var value = Uint8List.fromList(data);
    print("stream.value: $value"); // stream.value: [33]
    var hr = ByteData.sublistView(value,1);
    print("Heart rate: ${hr.getUint8(0)}");
    return hr.getUint8(0); // Heart rate: 33
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,appBar: AppBar(
        backgroundColor: const Color(0xffE5E0A1),elevation: 0,centerTitle: true,title: Text(
          "Configuration",style: TextStyle(
            fontSize: 15.0,color: Colors.black,fontFamily: 'Montserrat',fontWeight: FontWeight.normal,),leading: IconButton(
          icon: Icon(
            Icons.arrow_back,onpressed: () {
            Navigator.push(
              context,MaterialPageRoute(
                builder: (context) {
                  return ConfigurationScreen();
                },);
          },body: Column(
        children: [
          Container(
            padding: EdgeInsets.only(top: 65),alignment: Alignment.center,child: Text(
              'Device setting up...',style: TextStyle(
                fontFamily: 'Montserrat',fontWeight: FontWeight.w600,fontSize: 17,color: const Color(0xa8000000),height: 1.3333333333333333,textHeightBehavior:
                  TextHeightBehavior(applyHeightToFirstAscent: false),textAlign: TextAlign.center,Container(
            padding: EdgeInsets.symmetric(vertical: 120),child: const SpinKitFadingCircle(
              color: const Color(0xffF1C40E),size: 200,StreamBuilder<List<int>>(
            stream: stream,initialData: lastValue,builder: (BuildContext context,AsyncSnapshot<List<int>> snapshot) {
              var currentValue = _dataParser(snapshot.data);
              if (currentValue == 1) {
                print("Test Conf 1");
                Navigator.push(
                  context,MaterialPageRoute(
                    builder: (context) {
                      return confdeviceDone(
                        device: widget.device,);
                    },);
              }
            },],);
  }
}

设备完成屏幕代码

import 'package:epicare/Homepage.dart';
import 'package:Flutter/material.dart';
import 'package:Flutter_blue/Flutter_blue.dart';

import 'ConfigurationScreen.dart';

class confdeviceDone extends StatefulWidget {
  const confdeviceDone({Key key,this.device}) : super(key: key);
  final BluetoothDevice device;
  @override
  _confdeviceDonestate createState() => _confdeviceDonestate();
}

class _confdeviceDonestate extends State<confdeviceDone> {
  @override
  void initState() {
    // isReady = false;
    // discoverServices();
    var d = Duration(seconds: 2);
    // delayed 5 seconds to next page
    Future.delayed(d,() {
      // to next page and close this page
      Navigator.pushAndRemoveUntil(
        context,MaterialPageRoute(
          builder: (context) {
            return Homepage(device: widget.device);
          },(route) => false,);
    });

    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,child: Text(
              'Device Configured Successfully!',fontSize: 15,child: Image.asset('assets/images/green-tick.gif'),);
  }
}