android-studio - LiveQuery 不起作用，如果提供了 ParseConnectivityProvider

Question

我正在开发一个 Flutter 应用程序，它由一个带有 Parse Server 背景的员工调度程序组成。该应用程序的工作原理如下:
1)用户打开应用程序；
2)该应用程序显示可用员工的卡片列表(如果服务器数据库中有一些)
3) 用户可以编辑、确认或删除员工可用性。
该应用程序正在运行。这意味着我也可以像从我的应用程序屏幕一样从我的解析服务器获取 CRUD 数据。
目标 :数据库中的每个数据更改都需要刷新(实时)用户屏幕，移除、删除或更新(更改的)数据本身。
我的想法 :使用 parse_server_sdk: ^2.0.1 作为依赖项(pubspec.yaml)并实现实时查询(如 github 文档 here)
问题 :编译后，尽管我的 AndroidStudio 在视觉上没有崩溃，我的应用程序本身也没有崩溃，但它向我显示(日志)“LiveQuery 不起作用，如果提供了 ParseConnectivityProvider”。
没有问题(main.dart):

void main() async{

  runApp(MyApp());
}

导致问题:

void main() async{

//the following parameters are in other file (constants.dart)...they are working

  Parse().initialize(
    kParseApplicationId,
    kParseServerUrl,
    masterKey: kParseMasterKey,
    clientKey: kParseClientKey,
    debug: true,
    liveQueryUrl: kLiveQueryUrl,
    autoSendSessionId: true,
  );

  var dietPlan = ParseObject('DietPlan')
    ..set('Name', 'Ketogenic')
    ..set('Fat', 65);
  await dietPlan.save();

  var response = await dietPlan.save();
  if (response.success) {
    dietPlan = response.result;
  }

  //until here, the program works well.The data is inserted and retrieved, ok...but exactly here..the problem!

  final LiveQuery liveQuery = LiveQuery(); //from here..this is causing problems

  QueryBuilder<ParseObject> query =
  QueryBuilder<ParseObject>(ParseObject('DietPlan'))
    ..whereEqualTo('intNumber', 1);

  Subscription subscription = await liveQuery.client.subscribe(query);

  subscription.on(LiveQueryEvent.delete, (value) {
    print('*** DELETE ***: ${DateTime.now().toString()}\n $value ');
    print((value as ParseObject).objectId);
    print((value as ParseObject).updatedAt);
    print((value as ParseObject).createdAt);
    print((value as ParseObject).get('objectId'));
    print((value as ParseObject).get('updatedAt'));
    print((value as ParseObject).get('createdAt'));
  });

  runApp(MyApp());
}

我没有找到任何解决方案 googleing.Any 。经过多次研究，我得到(深入库)Parse.Initialize(...) 将connectivityProvider 作为其参数之一，但我没有填写该参数。
此外，当我插入该行时，问题就开始了:

final LiveQuery liveQuery = LiveQuery();

有人可以帮我解决这个问题吗？提前致谢
在下面，我展示了我的所有代码(main.dart):

// Copyright 2018 The Flutter team. 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:convert';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_datetime_picker/flutter_datetime_picker.dart';
import 'package:intl/intl.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:marca_horario/model/data.dart';
import 'package:marca_horario/network_utils/data_utils.dart';
import 'package:http/http.dart';
import 'package:parse_server_sdk/parse_server_sdk.dart';
import 'package:marca_horario/constants.dart';

void myLQ() async {
  Parse().initialize(
    kParseApplicationId,
    kParseServerUrl,
    masterKey: kParseMasterKey,
    clientKey: kParseClientKey,
    debug: true,
    liveQueryUrl: kLiveQueryUrl,
    autoSendSessionId: true,
  );

  var dietPlan = ParseObject('DietPlan')
    ..set('Name', 'Ketogenic')
    ..set('Fat', 65);
  await dietPlan.save();

  var response = await dietPlan.save();
  if (response.success) {
    dietPlan = response.result;
  }

  final LiveQuery liveQuery = LiveQuery();

  QueryBuilder<ParseObject> query =
  QueryBuilder<ParseObject>(ParseObject('DietPlan'))
    ..whereEqualTo('intNumber', 1);

  Subscription subscription = await liveQuery.client.subscribe(query);

  subscription.on(LiveQueryEvent.delete, (value) {
    print('*** DELETE ***: ${DateTime.now().toString()}\n $value ');
    print((value as ParseObject).objectId);
    print((value as ParseObject).updatedAt);
    print((value as ParseObject).createdAt);
    print((value as ParseObject).get('objectId'));
    print((value as ParseObject).get('updatedAt'));
    print((value as ParseObject).get('createdAt'));
  });
}


void main() async{

  Parse().initialize(
    kParseApplicationId,
    kParseServerUrl,
    masterKey: kParseMasterKey,
    clientKey: kParseClientKey,
    debug: true,
    liveQueryUrl: kLiveQueryUrl,
    autoSendSessionId: true,
  );

  var dietPlan = ParseObject('DietPlan')
    ..set('Name', 'Ketogenic')
    ..set('Fat', 65);
  await dietPlan.save();

  var response = await dietPlan.save();
  if (response.success) {
    dietPlan = response.result;
  }

  final LiveQuery liveQuery = LiveQuery();

  QueryBuilder<ParseObject> query =
  QueryBuilder<ParseObject>(ParseObject('DietPlan'))
    ..whereEqualTo('intNumber', 1);

  Subscription subscription = await liveQuery.client.subscribe(query);

  subscription.on(LiveQueryEvent.delete, (value) {
    print('*** DELETE ***: ${DateTime.now().toString()}\n $value ');
    print((value as ParseObject).objectId);
    print((value as ParseObject).updatedAt);
    print((value as ParseObject).createdAt);
    print((value as ParseObject).get('objectId'));
    print((value as ParseObject).get('updatedAt'));
    print((value as ParseObject).get('createdAt'));
  });

  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        localizationsDelegates: [
          GlobalMaterialLocalizations.delegate,
          GlobalWidgetsLocalizations.delegate
        ],
        supportedLocales: [const Locale('pt', 'BR')],
        home: Home()
    );
  }
}

class Home extends StatefulWidget {

  @override
  _HomeState createState() => _HomeState();
}

class _HomeState extends State<Home> {

  var _listTiles = List<String>();
  Color _iconColor = Colors.black;
  Color standardIconColor = Colors.black;
  Color alternateIconColor = Colors.green;
  TextEditingController _nameController = TextEditingController();
  var _scaffoldKey = new GlobalKey<ScaffoldState>();
  String standardTileTitle = "Adicione um horário disponível...";
  String _titleTile = "Adicione um horário disponível...";
  String _tileSubtitle = "Edite o nome do funcionário...";
  int _selectedIndexBottomNavBar = 0;
  final GlobalKey<RefreshIndicatorState> _refreshIndicatorKey = new GlobalKey<RefreshIndicatorState>();

  @override
  Widget build(BuildContext context) {
    return RefreshIndicator(
        key: _refreshIndicatorKey,
        onRefresh: () async {
          setState(() {

        });},
        child: Scaffold(
            key: _scaffoldKey,
            floatingActionButton: FloatingActionButton(
              onPressed: () {
                invokeDatePicker();
              },
              child: Icon(Icons.add),
            ),
            bottomNavigationBar: bottomNavigationBar(),
            appBar: AppBar(
              title: Text('Marca Horário'),
            ),
            // body: Center(
            //   child: Text('Hello World'),
            body: bodyStartScreen()
        ),
    );
  }


  Widget bottomNavigationBar(){

    void _onItemTapped(int index) {
      setState(() {
        _selectedIndexBottomNavBar = index;
      });
      print(_selectedIndexBottomNavBar);
      if(_selectedIndexBottomNavBar == 2){
        DatePicker.showDateTimePicker(context,
            showTitleActions: true,
            minTime: DateTime(2020, 1, 1),
            maxTime: DateTime(2021, 12, 31),
            onChanged: (date) {
              print('change $date');
            },
            onConfirm: (date) {
              print('confirm $date');
              _listTiles.add(DateFormat.yMMMEd('pt_BR').add_Hm().format(date).toString());
              _titleTile = DateFormat.yMMMEd('pt_BR').add_Hm().format(date).toString();

              setState(() {

              });
            },
            currentTime: DateTime.now(),
            locale: LocaleType.pt);
      }
    }

    return BottomNavigationBar(
      items: const <BottomNavigationBarItem>[
        BottomNavigationBarItem(
          icon: Icon(Icons.home),
          label: 'Home',
        ),
        BottomNavigationBarItem(
          icon: Icon(Icons.person),
          label: 'Funcionário',
        ),
        BottomNavigationBarItem(
          icon: Icon(Icons.access_time),
          label: 'Marcar',
        ),
      ],
      currentIndex: _selectedIndexBottomNavBar,
      selectedItemColor: Colors.amber[800],
      onTap: _onItemTapped,
    );
  }

  Widget bodyStartScreen(){
    return Column(
      children: [
        //the main title of the screen
        Padding(
          padding: EdgeInsets.all(16.0),
          child: Text("Horários Possíveis",
            style: TextStyle(
                fontSize: 18.0
            ),
          ),
        ),
        //gets available employees and datetimes from the server
        FutureBuilder(builder: (context,snapshot){
          if (snapshot.data != null) {
            List<Data> dataList = snapshot.data;

            return Expanded(
              child: ListView.builder(
                itemBuilder: (_, position) {
                return Card(
                  child: ListTile(
                    title: Text(dataList[position].dateTime),
                    subtitle: Text(dataList[position].employee),
                    trailing: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: <Widget>[
                        IconButton(icon: Icon(Icons.edit), onPressed: () {
                          //Show dialog box to update item
                          showUpdateDialog(dataList[position]);
                        }),
                        IconButton(icon: Icon(Icons.check_circle, color: Colors.green,), onPressed: () {

                        }),
                        //Show dialog box to delete item
                        IconButton(icon: Icon(Icons.delete), onPressed: () {
                          deleteData(dataList[position].objectId);
                        }),
                      ],
                    ),
                  ),
                );
              },
                itemCount: dataList.length,
              ),
            );

          } else {
            return Center(
              child: CircularProgressIndicator(),
            );
          }
        },
          future: getDataList(),
        ),
        Divider(
          color: Colors.black,
        ),
        scheduleTile()
      ],
    );
  }

  void invokeDatePicker(){
    DatePicker.showDateTimePicker(context,
        showTitleActions: true,
        minTime: DateTime(2020, 1, 1),
        maxTime: DateTime(2021, 12, 31),
        onChanged: (date) {
          print('change $date');
        },
        onConfirm: (date) {
          print('confirm $date');
          _listTiles.add(DateFormat.yMMMEd('pt_BR').add_Hm().format(date).toString());
          _titleTile = DateFormat.yMMMEd('pt_BR').add_Hm().format(date).toString();

          setState(() {

          });
        },
        currentTime: DateTime.now(),
        locale: LocaleType.pt);
  }

  void showUpdateDialog(Data data) {

    _nameController.text = data.employee;

    showDialog(context: context,
        builder: (_) => AlertDialog(
          content: Container(
            width: double.maxFinite,
            child: TextField(
              controller: _nameController,
              decoration: InputDecoration(
                labelText: "Atualizar funcionário disponível",
              ),
            ),
          ),
          actions: <Widget>[
            FlatButton(onPressed: () {
              Navigator.pop(context);
              data.employee = _nameController.text;
              updateData(data);
            }, child: Text("Atualizar")),
            FlatButton(onPressed: () {
              Navigator.pop(context);
            }, child: Text("Cancelar")),
          ],
        )
    );

  }

  Widget scheduleTile(){
    return Padding(
      padding: EdgeInsets.only(bottom: 80.0),
      child: Card(
        color: Colors.grey,
        child: ListTile(
          title: Text(_titleTile),
          subtitle: Text(_tileSubtitle),
          trailing: Row(
            mainAxisSize: MainAxisSize.min,
            children: <Widget>[
              IconButton(
                icon: Icon(
                  Icons.edit,
                  color: standardIconColor,
                  size: 20.0,
                ),
                onPressed: () {
                  setState(() {
                    employeeAvailable();
                  });
                },
              ),
              IconButton(
                icon: Icon(
                  Icons.check_circle_outline,
                  color: _iconColor,
                  size: 20.0,
                ),
                onPressed: () {
                  setState(() {
                    (_titleTile != standardTileTitle) ? confirmSchedule() : fillTimeDialog();
                  });
                },
              )
            ],
          ),
        ),
      ),
    );
  }

  void fillTimeDialog(){
    showDialog(context: context,
        builder: (_) => AlertDialog(
          content: Container(
            width: double.maxFinite,
            child: Text("Insira o horário disponível!"),
          ),
          actions: <Widget>[
            FlatButton(onPressed: () {
              Navigator.pop(context);
            }, child: Text("OK")),
          ],
        )
    );
  }

  void employeeAvailable(){
    showDialog(context: context,
        builder: (_) => AlertDialog(
          content: Container(
            width: double.maxFinite,
            child: TextField(
              controller: _nameController,
              decoration: InputDecoration(
                labelText: "Funcionário",
              ),
            ),
          ),
          actions: <Widget>[
            FlatButton(onPressed: () {

              Navigator.pop(context);
              //addTodo();
              setState(() {
                _tileSubtitle = "Disponível: " + _nameController.text;
              });

            }, child: Text("Inserir")),
            FlatButton(onPressed: () {
              Navigator.pop(context);
              setState(() {
                _tileSubtitle = " ";
              });

            }, child: Text("Desfazer")),
          ],
        )
    );
  }

  void confirmSchedule(){
    showDialog(context: context,
        builder: (_) => AlertDialog(
          content: Container(
            width: double.maxFinite,
            child: Text("Confirma disponibilidade?")
          ),
          actions: <Widget>[
            FlatButton(onPressed: () {
              Navigator.pop(context);
              //addTodo();
              addData();
              setState(() {
                _iconColor = alternateIconColor;
                _tileSubtitle = "Disponível: " + _nameController.text;
              });

            }, child: Text("Confirma")),
            FlatButton(onPressed: () {
              Navigator.pop(context);
              setState(() {
                _iconColor = standardIconColor;
                _tileSubtitle = " ";
              });

            }, child: Text("Não")),
          ],
        )
    );
  }

  void addData() {

    _scaffoldKey.currentState.showSnackBar(SnackBar(content: Row(
      children: <Widget>[
        Text("Adicionando informações..."),
        CircularProgressIndicator(),
      ],
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
    ),
      duration: Duration(minutes: 1),
    ));

    Data data = Data(employee: _tileSubtitle, dateTime: _titleTile);

    DataUtils.addData(data)
        .then((res) {

      _scaffoldKey.currentState.hideCurrentSnackBar();

      Response response = res;
      if (response.statusCode == 201) {
        //Successful
        _nameController.text = "";

        _scaffoldKey.currentState.showSnackBar(SnackBar(content: Text("Informações disponibilizadas!"), duration: Duration(seconds: 1),));

        setState(() {
          //Update UI
        });

      }

    });

  }

  void deleteData(String objectId) {

    _scaffoldKey.currentState.showSnackBar(SnackBar(content: Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children:  <Widget>[
        Text("Excluindo disponibilidade..."),
        CircularProgressIndicator(),
      ],
    ),
      duration: Duration(minutes: 1),
    ),);


    DataUtils.deleteData(objectId)
        .then((res) {

      _scaffoldKey.currentState.hideCurrentSnackBar();

      Response response = res;
      if (response.statusCode == 200) {
        //Successfully Deleted
        _scaffoldKey.currentState.showSnackBar(SnackBar(content: (Text("Disponibilidade excluída!")),duration: Duration(seconds: 1),));
        setState(() {

        });
      } else {
        //Handle error
      }
    });

  }

  void updateData(Data data) {

    _scaffoldKey.currentState.showSnackBar(SnackBar(content: Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: <Widget>[
        Text("Atualizando disponibilidade..."),
        CircularProgressIndicator(),
      ],
    ),
      duration: Duration(minutes: 1),
    ),);


    DataUtils.updateData(data)
        .then((res) {

      _scaffoldKey.currentState.hideCurrentSnackBar();

      Response response = res;
      if (response.statusCode == 200) {
        //Successfully Deleted
        _nameController.text = "";
        _scaffoldKey.currentState.showSnackBar(SnackBar(content: (Text("Disponibilidade atualizada!"))));
        setState(() {

        });
      } else {
        //Handle error
      }
    });

  }

  Future <List<Data>> getDataList() async{

    List<Data> dataList = [];

    Response response = await DataUtils.getDataList();
    print("Code is ${response.statusCode}");
    print("Response is ${response.body}");

    if (response.statusCode == 200) {
      var body = json.decode(response.body);
      var results = body["results"];

      for (var data in results) {
        dataList.add(Data.fromJson(data));
      }

    } else {
      //Handle error
    }

    return dataList;
  }
}

data_utils.dart:

import 'dart:convert';

import 'package:http/http.dart';
import 'package:marca_horario/model/data.dart';
import 'package:marca_horario/constants.dart';

class DataUtils {

  //static final String _baseUrl = "https://parseapi.back4app.com/classes/";
  static final String _baseUrl = baseUrl;

  //CREATE
  static Future<Response> addData(Data data) async {
    String apiUrl = _baseUrl + "Data";

    Response response = await post(apiUrl,
      headers: {
        'X-Parse-Application-Id': kParseApplicationId,
        'X-Parse-REST-API-Key': kParseRestApiKey,
        'Content-Type': 'application/json'
      },
      body: json.encode(data.toJson()),
    );

    return response;
  }

  //READ
  static Future getDataList() async{

    String apiUrl = _baseUrl + "Data";

    Response response = await get(apiUrl, headers: {
      'X-Parse-Application-Id' : kParseApplicationId,
      'X-Parse-REST-API-Key' : kParseRestApiKey,
    });

    return response;
  }

  //UPDATE
  static Future updateData(Data data) async{

    String apiUrl = _baseUrl + "Data/${data.objectId}";

    Response response = await put(apiUrl, headers: {
      'X-Parse-Application-Id' : kParseApplicationId,
      'X-Parse-REST-API-Key' : kParseRestApiKey,
      'Content-Type' : 'application/json',
    },
        body: json.encode(data.toJson())
    );

    return response;
  }

  //DELETE
  static Future deleteData(String objectId) async{

    String apiUrl = _baseUrl + "Data/$objectId";

    Response response = await delete(apiUrl, headers: {
      'X-Parse-Application-Id' : kParseApplicationId,
      'X-Parse-REST-API-Key' : kParseRestApiKey,
    });

    return response;
  }
}

Answer 1

问题解决了!
我的问题是:import 'package:parse_server_sdk/parse_server_sdk.dart';需要替换为:import 'package:parse_server_sdk_flutter/parse_server_sdk.dart';在 pubspec.yaml 中，只需要使用对应的依赖项:parse_server_sdk_flutter: ^2.0.1