如何通过firebase（ios）与Flatter进行实时聊天

我为每个订单的用户和供应商之间的颤振应用程序制作了聊天模块，但在真正的iPhone中，我需要返回，然后打开聊天屏幕才能看到新消息，而不是实时的

如何将其转换为实时信息，以便用户或供应商无需返回，然后重新打开聊天页面以查看新消息

这是我的密码

用户聊天屏幕

import 'dart:async';
import 'dart:io';
import 'dart:math';
import 'dart:convert';
import 'dart:async' show Future;
import 'package:http/http.dart' as http;
import 'package:flutter/material.dart';
import 'package:firebase_database/firebase_database.dart';
import 'package:intl/intl.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'chat_model.dart';
import 'chatmessage.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:uuid/uuid.dart';
import 'package:keyboard_actions/keyboard_actions.dart';

class ChatPage extends StatefulWidget {
  final String _userName;
  final String _id;
  final String _userid;
  final String _orderNo;
  final String vendorId;

  //widget.vendorId

  ChatPage(
      this._userName, this._id, this._userid, this._orderNo, this.vendorId);

  StreamSubscription _subscriptionTodo;

  @override
  _ChatPageState createState() => new _ChatPageState();
}

class _ChatPageState extends State<ChatPage> {
  static var databaseReference = FirebaseDatabase.instance.reference();
  var v_id;
  var vendor_id;
  var user_id;
  var vendor_name, vendor_token;
  final TextEditingController _chatController = new TextEditingController();
  final List<ChatMessage> _messages = <ChatMessage>[];
  List<ChatModel> list_messages = List<ChatModel>();

  DateTime now = DateTime.now();
  FirebaseMessaging _firebaseMessaging = FirebaseMessaging();
  FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;
  var chat_id_fr;

  Future onSelectNotification(String payload) {
    debugPrint("payload : $payload");
    showDialog(
      context: context,
      builder: (_) => new AlertDialog(
            title: new Text('Notification'),
            content: new Text('$payload'),
          ),
    );
  }

  @override
  void initState() {
    vendor_id = widget.vendorId;
    user_id = widget._userid;

    print(vendor_id + "ssssss");

    getDetails();
    getchat();

    flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();
    var android = new AndroidInitializationSettings('@mipmap/ic_launcher');
    var iOS = new IOSInitializationSettings();
    var initSetttings = new InitializationSettings(android, iOS);
    flutterLocalNotificationsPlugin.initialize(initSetttings,
        onSelectNotification: onSelectNotification);

    //_firebaseMessaging.setAutoInitEnabled(enabled)
    _firebaseMessaging.configure(
      onLaunch: (Map<String, dynamic> message) {
        print('onLaunch called');
        showNotification("", "");
      },
      onResume: (Map<String, dynamic> message) {
        print('onResume called');
        showNotification("", "");
      },
      onMessage: (Map<String, dynamic> message) {
        print('onMessage called' + message.toString());

        Map msg_ = message['notification'];
        String body = msg_['body'];
        String title = msg_['title'];


        setState(() {
          ChatMessage message = new ChatMessage(
            text: body.toString(),
            vendor: "vendor",
            vendor_name: "",
          );
          print("msg===" + body.toString());
          print("msg===" + body.toString());
          _messages.insert(0, message);
          showNotification(body, title);
        });

      },
    );
    _firebaseMessaging.subscribeToTopic('all');
    _firebaseMessaging.requestNotificationPermissions(IosNotificationSettings(
      sound: true,
      badge: true,
      alert: true,
    ));
    _firebaseMessaging.onIosSettingsRegistered
        .listen((IosNotificationSettings settings) {
      print('Hello');
    });
    _firebaseMessaging.getToken().then((token) {});
  }

  showNotification(String body, String title) async {
    var android = new AndroidNotificationDetails(
        'channel id', 'channel NAME', 'CHANNEL DESCRIPTION',
        priority: Priority.High, importance: Importance.Max);
    var iOS = new IOSNotificationDetails();
    var platform = new NotificationDetails(android, iOS);
    await flutterLocalNotificationsPlugin
        .show(0, 'New Message', '$body', platform, payload: '$body');
  }

  Future<String> getDetails() async {
    FirebaseDatabase.instance
        .reference()
        .child("vendor")
        .child(vendor_id)
        .once()
        .then((DataSnapshot snapshot) {
      Map value = snapshot.value;
      var vendor_id_fr = value['id'];
      vendor_name = value['name'];
      vendor_token = value['token'];

      //Map<String, dynamic> data = map['Data'];
      print("name " + vendor_name);
      print("id " + vendor_id);
      print("token " + vendor_token);
    });

    return vendor_id.toString();
  }

  Future<String> getchat() async {
    FirebaseDatabase.instance
        .reference()
        .child("chat")
        .child(widget._orderNo)
        .once()
        .then((DataSnapshot snapshot) {
      Map value_ = snapshot.value;
      value_.forEach((key, value) {
        Map value_1 = value;
        chat_id_fr = value_1['chat_id'];
        var vendor_msg_fr = value_1['msg'];
        var user_id_ = value_['user_id'];
        var vendor_id_ = value_['vendor_id'];

        ChatModel chatModel = new ChatModel.fromJson(value);

        list_messages.add(chatModel);
        list_messages.sort((x, y) => x.chat_id_fr.compareTo(y.chat_id_fr));


      });

      var list_data = list_messages.toString();

      print(list_data.toString());
      // list_messages=list_messages.reversed.toList();

      int dfd = list_messages.length;

      for (int i = 0; i <= list_messages.length; i++) {
        dfd = dfd - 1;

      /*  var value = list_messages.reduce((curr, next) => curr.chat_id_fr > next.chat_id_fr ? curr : next);
        var value1 = list_messages.reduce((curr, next) => curr.chat_id_fr > next.chat_id_fr ? curr : next);
*/


        if (list_messages
            .elementAt(dfd)
            .for_value
            .toString()
            .contains("user")) {
          setState(() {
            ChatMessage message = new ChatMessage(
                text: list_messages.elementAt(dfd).msg,
                vendor: "user",
                vendor_name: vendor_name);
            _messages.add(message);
          });
        } else {
          setState(() {
            ChatMessage message = new ChatMessage(
              text: list_messages.elementAt(dfd).msg.toString(),
              vendor: "vendor",
              vendor_name: vendor_name,
            );
            _messages.add(message);
            //list_messages.reversed.toList();
          });
        }
      }
    });

    return vendor_id.toString();
  }

  Future<http.Response> postRequest(String msg) async {
    var url = 'https://fcm.googleapis.com/fcm/send';

    Map<String, dynamic> jsonMap = {
      'notification': {'body': '$msg', 'title': 'New Massage'},
      'to':
          'fPgRVKZY56Q:APA91bHEMQy1EKHbPUraCn2tCp2th6Oah5Xx_N7b-6wLiHWjjYG7WCaRmjwstR8_YaNukwA_mwZHuCpQoYKuXL7nQBMGPH3kw58vHth7FkXuyn-keW0JnNUZhDzlgV2RA9HraeW2M4R0',
    };
    Map<String, dynamic> jsonMap1 = {
      'notification': {'body': '$msg', 'title': 'New Massage'},
      'to': '$vendor_token',
    };

    //encode Map to JSON
    var body = json.encode(jsonMap1);
    var response = await http.post(url,
        headers: {
          "Content-Type": "application/json",
          "Authorization":
              "key=AAAAt08dld0:APA91bEY6Dtrb1x1SlAprnEYeSEUdCT0D0oq9qzlkLJDIJdB0-hVIbdKL_L6CysecmOb46gjD3lyZMKl5aGH4rY1daFYA838VMnS7SzumelXie3Vps7s8MkILRgz7Kj0QQ65Dp0uZLI6"
        },
        body: body);
    print("${response.statusCode}" + "=response=");
    print("${response.body}" + "=response=");
    return response;
  }

  void _handleSubmit(String text) {
    _chatController.clear();

    String formattedDate = DateFormat('kk:mm:ss').format(now).toString();

    var uuid = new Uuid();

    var rondm_no;
    var rng = new Random();

    for (var i = 0; i < 10; i++) {
      print(rng.nextInt(100));
      rondm_no = uuid.v1().toString() + 'user_id';
    }

   // chat_id_fr = 0;

    if (_messages.length == 0) {
      databaseReference
          .child("chat")
          .child(widget._orderNo)
          .child('$rondm_no')
          .update({
        'vendor_id': vendor_id.toString(),
        'user_id': user_id.toString(),
        'msg': text.toString(),
        'chat_id': 0,
        'for_value': 'user',
      });

      setState(() {
        ChatMessage message = new ChatMessage(
          text: text.toString(),
          vendor: "user",
          vendor_name: "",
        );
        postRequest(text.toString());
        print("msg===" + text.toString());
        print("msg===" + text.toString());
        _messages.insert(0, message);
      });
    } else {
      for (var i = 0; i < _messages.length; i++) {
        int chat_id_fr = i + 1;

        databaseReference
            .child("chat")
            .child(widget._orderNo)
            .child('$rondm_no')
            .update({
          'vendor_id': vendor_id.toString(),
          'user_id': user_id.toString(),
          'msg': text.toString(),
          'chat_id': chat_id_fr,
          'for_value': 'user',
        });
      }

      setState(() {
        ChatMessage message = new ChatMessage(
          text: text.toString(),
          vendor: "user",
          vendor_name: "",
        );
        postRequest(text.toString());
        print("msg===" + text.toString());
        print("msg===" + text.toString());
        _messages.insert(0, message);
      });
    }


  }

  Widget _chatEnvironment() {
    return IconTheme(
      data: new IconThemeData(color: Color(0xFF7872c0)),
      child: new Container(
        margin: const EdgeInsets.symmetric(horizontal: 8.0),
        child: new Row(
          children: <Widget>[
            new Flexible(
              child: new TextField(
                decoration: new InputDecoration.collapsed(
                    hintText: "Starts typing ..."),
                controller: _chatController,
                onSubmitted: _handleSubmit,
              ),
            ),
            new Container(
              margin: const EdgeInsets.symmetric(horizontal: 4.0),
              child: new IconButton(
                icon: new Icon(Icons.send),
                onPressed: () => _handleSubmit(_chatController.text),
              ),
            )
          ],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
          title: new Text("المحادثة"), //Conversation
          backgroundColor: Color(0xFF7872c0),
        ),
        body: new Column(
          children: <Widget>[
            new Flexible(
              child: ListView.builder(
                padding: new EdgeInsets.all(8.0),
                reverse: true,
                itemBuilder: (_, int index) => _messages[index],
                itemCount: _messages.length,
              ),
            ),
            new Divider(
              height: 1.0,
            ),
            new Container(
              decoration: new BoxDecoration(
                color: Theme.of(context).cardColor,
              ),
              child: _chatEnvironment(),
            )
          ],
        ));
  }
}

import 'dart:async';
import 'dart:math';
import 'dart:async';
import 'dart:io';
import 'dart:math';
import 'dart:convert';
import 'dart:async' show Future;
import 'package:firebase_database/firebase_database.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import 'package:koni_app/Pages/UsersPages/MyOrders/Chat.dart';
import 'package:koni_app/Pages/UsersPages/MyOrders/chat_model.dart';
import 'package:koni_app/Pages/UsersPages/MyOrders/chatmessage.dart';
import 'package:http/http.dart' as http;
import 'MyOrders/Vendorchatmessage.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:uuid/uuid.dart';
import 'package:keyboard_actions/keyboard_actions.dart';
import 'MyOrders/vendorchat_model.dart';

class VendorAdminChatPage extends StatefulWidget {
  final String _userName;
  final String _id;
  final String _userid;
  final String orderNo;
  final String vendorId;
  VendorAdminChatPage(this._userName, this._id, this._userid, this.orderNo,this.vendorId);

  StreamSubscription _subscriptionTodo;

/*
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Color(0xFF7872c0),
        title: Text("تواصل مع الادارة "),
      ),
      body: Center(
        child: Text('here the UserAdminChat page it will be '),
      ),
    );
  }
*/

  @override
  State<StatefulWidget> createState() {
    // TODO: implement createState
    return _VendorChatPageState();
  }
}

class _VendorChatPageState extends State<VendorAdminChatPage> {
  static var databaseReference = FirebaseDatabase.instance.reference();
  var v_id;
  var vendor_id;
  var user_id;
  var user_name, user_token;

  final TextEditingController _chatController = new TextEditingController();
  final List<Vendorchatmessage> _messages = <Vendorchatmessage>[];

  FirebaseMessaging _firebaseMessaging = FirebaseMessaging();
  List<VendorChatModel> list_messages = List<VendorChatModel>();

  DateTime now = DateTime.now();
  FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;

  int chat_id_fr;

  Future onSelectNotification(String payload) {
    debugPrint("payload : $payload");
    showDialog(
      context: context,
      builder: (_) => new AlertDialog(
            title: new Text('Notification'),
            content: new Text('$payload'),
          ),
    );
  }

  @override
  void initState() {
    vendor_id = widget.vendorId;
    user_id = widget._userid;
    user_id = widget._userid;
    // var user_Id = widget._userid;
    print("sssss" + user_id);

    getDetails();
    getchat();

    flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();
    var android = new AndroidInitializationSettings('@mipmap/ic_launcher');
    var iOS = new IOSInitializationSettings();
    var initSetttings = new InitializationSettings(android, iOS);
    flutterLocalNotificationsPlugin.initialize(initSetttings,
        onSelectNotification: onSelectNotification);


    _firebaseMessaging.configure(
      onLaunch: (Map<String, dynamic> message) {
        print('onLaunch called');
        showNotification("", "");
      },
      onResume: (Map<String, dynamic> message) {
        print('onResume called');
        showNotification("", "");
      },
      onMessage: (Map<String, dynamic> message) {
        print('onMessage called' + message.toString());

        Map msg_ = message['notification'];
        String body = msg_['body'];
        String title = msg_['title'];



        setState(() {
          showNotification(body, title);
          Vendorchatmessage message = new Vendorchatmessage(
            text: body.toString(),
            vendor: "user",
            vendor_name: "",
          );
          print("msg===" + body.toString());
          print("msg===" + body.toString());
          _messages.insert(0, message);
        });

      },
    );
    _firebaseMessaging.subscribeToTopic('all');
    _firebaseMessaging.requestNotificationPermissions(IosNotificationSettings(
      sound: true,
      badge: true,
      alert: true,
    ));
    _firebaseMessaging.onIosSettingsRegistered
        .listen((IosNotificationSettings settings) {
      print('Hello');
    });
    _firebaseMessaging.getToken().then((token) {});
  }

  showNotification(String body, String title) async {
    var android = new AndroidNotificationDetails(
        'channel id', 'channel NAME', 'CHANNEL DESCRIPTION',
        priority: Priority.High, importance: Importance.Max);
    var iOS = new IOSNotificationDetails();
    var platform = new NotificationDetails(android, iOS);
    await flutterLocalNotificationsPlugin
        .show(0, 'New Message', '$body', platform, payload: '$body');
  }

  Future<String> getDetails() async {
    FirebaseDatabase.instance
        .reference()
        .child("user")
        .child(user_id)
        .once()
        .then((DataSnapshot snapshot) {
      Map value = snapshot.value;
      var vendor_id_fr = value['id'];
      user_name = value['name'];
      user_token = value['token'];

      //Map<String, dynamic> data = map['Data'];
      print("name " + user_name);
      print("id " + vendor_id);
      print("token " + user_token);
    });
    return vendor_id.toString();
  }

  Future<String> getchat() async {
    FirebaseDatabase.instance
        .reference()
        .child("chat")
        .child(widget.orderNo)
        .once()
        .then((DataSnapshot snapshot) {
      Map value_ = snapshot.value;

      value_.forEach((key, value) {
        Map value_1 = value;

        chat_id_fr = value_1['chat_id'];
        var vendor_msg_fr = value_1['msg'];
        var user_id_ = value_['user_id'];
        var vendor_id_ = value_['vendor_id'];

        VendorChatModel chatModel = new VendorChatModel.fromJson(value);
        list_messages.add(chatModel);
        list_messages.sort((a, b) => a.chat_id_fr.compareTo(b.chat_id_fr));

      });

      var list_data = list_messages.toString();
      print(list_data.toString());
      int dfd = list_messages.length;

      for (int i = 0; i <= list_messages.length; i++) {

      /*  String lower=list_messages.elementAt(0).chat_id_fr;
        String lower1=list_messages.elementAt(0).chat_id_fr;
*/
        dfd = dfd - 1;


       /* int ss=list_messages.length-1;
        String ss=ss.toString();*/

        if (list_messages.elementAt(dfd).for_value.toString().contains("user")) {

          setState(() {
            Vendorchatmessage message = new Vendorchatmessage(
                text: list_messages.elementAt(dfd).msg,
                vendor: "user",
                vendor_name: user_name);
            _messages.add(message);
          });

        } else {
          setState(() {
            Vendorchatmessage message = new Vendorchatmessage(
              text: list_messages.elementAt(dfd).msg,
              vendor: "vendor",
              vendor_name: user_name,
            );
            _messages.add(message);

          });
        }
      }
    });



    return vendor_id.toString();
  }

  void _handleSubmit(String text) {
    _chatController.clear();
    // Vendorchatmessage message = new Vendorchatmessage(text: text);
    String formattedDate = DateFormat('kk:mm:ss').format(now).toString();
    var rondm_no;
    var uuid = new Uuid();

    var rng = new Random();
    for (var i = 0; i < 10; i++) {
      print(rng.nextInt(100));
      rondm_no = uuid.v1().toString() + 'vendor_id';
    }

    chat_id_fr = 0;

    if (_messages.length == 0) {
      databaseReference
          .child("chat")
          .child(widget.orderNo)
          .child('$rondm_no')
          .update({
        'vendor_id': vendor_id.toString(),
        'user_id': user_id.toString(),
        'msg': text.toString(),
        'chat_id': 0,
        'for_value': 'vendor',
      });
    } else {
      for (var i = 0; i < _messages.length; i++) {
        chat_id_fr = i + 1;
        databaseReference
            .child("chat")
            .child(widget.orderNo)
            .child('$rondm_no')
            .update({
          'vendor_id': vendor_id.toString(),
          'user_id': user_id.toString(),
          'msg': text.toString(),
          'chat_id': chat_id_fr,
          'for_value': 'vendor',
        });
      }
    }

    /*databaseReference.child("chat").child(widget.orderNo).update({
      'vendor_id': vendor_id.toString(),
      'user_id': user_id.toString(),
    });*/

    setState(() {
      Vendorchatmessage message = new Vendorchatmessage(
        text: text.toString(),
        vendor: "vendor",
        vendor_name: "",
      );

      print("msg===" + text.toString());
      print("msg===" + text.toString());
      _messages.insert(0, message);

      postRequest(text.toString());
    });
  }

  Future<http.Response> postRequest(String msg) async {
    var url = 'https://fcm.googleapis.com/fcm/send';

    Map<String, dynamic> jsonMap1 = {
      'notification': {'body': '$msg', 'title': 'New Massage'},
      'to': '$user_token',
    };

    //encode Map to JSON
    var body = json.encode(jsonMap1);
    var response = await http.post(url,
        headers: {
          "Content-Type": "application/json",
          "Authorization":
              "key=AAAAt08dld0:APA91bEY6Dtrb1x1SlAprnEYeSEUdCT0D0oq9qzlkLJDIJdB0-hVIbdKL_L6CysecmOb46gjD3lyZMKl5aGH4rY1daFYA838VMnS7SzumelXie3Vps7s8MkILRgz7Kj0QQ65Dp0uZLI6"
        },
        body: body);
    print("${response.statusCode}" + "=response=");
    print("${response.body}" + "=response=");

    return response;
  }

  Widget _chatEnvironment() {
    return IconTheme(
      data: new IconThemeData(color: Color(0xFF7872c0)),
      child: new Container(
        margin: const EdgeInsets.symmetric(horizontal: 8.0),
        child: new Row(
          children: <Widget>[
            new Flexible(
              child: new TextField(
                decoration: new InputDecoration.collapsed(
                    hintText: "Starts typing ..."),
                controller: _chatController,
                onSubmitted: _handleSubmit,
              ),
            ),
            new Container(
              margin: const EdgeInsets.symmetric(horizontal: 4.0),
              child: new IconButton(
                icon: new Icon(Icons.send),
                onPressed: () => _handleSubmit(_chatController.text),
              ),
            )
          ],
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
          title: new Text("المحادثة"), //Conversation
          backgroundColor: Color(0xFF7872c0),
        ),
        body: new Column(
          children: <Widget>[
            new Flexible(
              child: ListView.builder(
                padding: new EdgeInsets.all(8.0),
                reverse: true,
                itemBuilder: (_, int index) => _messages[index],
                itemCount: _messages.length,
              ),
            ),
            new Divider(
              height: 1.0,
            ),
            new Container(
              decoration: new BoxDecoration(
                color: Theme.of(context).cardColor,
              ),
              child: _chatEnvironment(),
            )
          ],
        )

        /* Container(
          margin: const EdgeInsets.symmetric(horizontal: 8.0),
          child: Column(
            children: <Widget>[
              new Flexible(
                child: new ListView.builder(
                  padding: new EdgeInsets.all(8.0),
                  reverse: true,
                  itemBuilder: (_, int index) {},
                  itemCount: 10,
                ),
              ),
              new Divider(height: 1.0),
              Container(
                margin: EdgeInsets.only(bottom: 20.0, right: 10.0, left: 10.0),
                child: Row(
                  children: <Widget>[
                    new Flexible(
                      child: new TextField(
                        decoration: new InputDecoration.collapsed(
                            hintText: "ارسال الرسالة"), //"Send message"
                      ),
                    ),
                    new Container(
                      child: new IconButton(
                          icon: new Icon(
                            Icons.send,
                            color: Color(0xFF7872c0),
                          ),
                          onPressed: () {

                          }),
                    ),
                  ],
                ),
              ),
            ],
          ),
        )*/

        );
  }
}

导入'dart:async'；
导入“dart:io”；
导入“dart:math”；
导入“dart:convert”；
导入“dart:async”显示未来；
将“package:http/http.dart”导入为http；
进口“包装：颤振/材料.省道”；
导入“package:firebase_database/firebase_database.dart”；
导入“包：intl/intl.dart”；
导入“package:firebase_messaging/firebase_messaging.dart”；
导入“chat_model.dart”；
导入“chatmessage.dart”；
导入“package:flatter_local_notifications/flatter_local_notifications.dart”；
导入“包：uuid/uuid.dart”；
导入“包：键盘动作/键盘动作.dart”；
类ChatPage扩展StatefulWidget{
最终字符串\u用户名；
最终字符串_id；
最终字符串_userid；
最终字符串_orderNo；
最终字符串vendorId；
//widget.vendorId
聊天页(
这个。\用户名，这个。\ id，这个。\用户名，这个。\订单号，这个。供应商id）；
StreamSubscription _subscriptionTodo；
@凌驾
_ChatPageState createState（）=>新建；
}
类_ChatPageState扩展状态{
静态var databaseReference=FirebaseDatabase.instance.reference（）；
变量v_id；
var供应商id；
var用户id；
var供应商名称、供应商令牌；
最终文本编辑控制器_chatController=新文本编辑控制器（）；
最终列表_消息=[]；
List_messages=List（）；
DateTime now=DateTime.now（）；
FirebaseMessaging_FirebaseMessaging=FirebaseMessaging（）；
flatterlocalnotificationsplugin flatterlocalnotificationsplugin；
变量chat\u id\u fr；
未来onSelectNotification（字符串负载）{
debugPrint（“有效载荷：$payload”）；
显示对话框(
上下文：上下文，
生成器：（）=>新建警报对话框(
标题：新文本（“通知”），
内容：新文本（“$payload”），
),
);
}
@凌驾
void initState（）{
vendor_id=widget.vendorId；
用户标识=小部件。\用户标识；
打印（供应商id+“SSSS”）；
getDetails（）；
getchat（）；
FlatterLocalNotificationsPlugin=新的FlatterLocalNotificationsPlugin（）；
var android=新的AndroidInitializationSettings（“@mipmap/ic_launcher”）；
var iOS=新的IOSInitializationSettings（）；
var initSetttings=新的初始化设置（android、iOS）；
FlatterLocalNotificationsPlugin.initialize（初始化设置，
onSelectNotification：onSelectNotification）；
//_firebaseMessaging.setAutoInitEnabled（已启用）
_firebaseMessaging.configure(
onLaunch：（映射消息）{
打印（'onLaunch called'）；
显示通知（“，”）；
},
onResume：（映射消息）{
打印（'onResume called'）；
显示通知（“，”）；
},
onMessage：（映射消息）{
print（'onMessage调用'+message.toString（））；
映射消息=消息['notification']；
字符串body=msg_['body']；
String title=msg_389;['title']；
设置状态（）{
ChatMessage message=新建ChatMessage(
文本：body.toString（），
供应商：“供应商”，
供应商名称：“”，
);
打印（“msg==”+body.toString（））；
打印（“msg==”+body.toString（））；
_消息。插入（0，消息）；
展示通知（正文、标题）；
});
},
);
_firebaseMessaging.subscribeToTopic（'all'）；
_firebaseMessaging.requestNotificationPermissions（IONotificationSettings(
听起来：是的，
徽章：没错，
警报：是的，
));
_firebaseMessaging.onissettings已注册
.listen（（IONotificationSettings）{
打印（“你好”）；
});
_firebaseMessaging.getToken（）.then（（令牌）{}）；
}
showNotification（字符串正文、字符串标题）异步{
var android=新的AndroidNotificationDetails(
“频道id”、“频道名称”、“频道描述”，
优先级：优先级。高，重要性：重要性。最大）；
var iOS=新的IONotificationDetails（）；
var平台=新通知详细信息（android、iOS）；
等待通知
.show（0，'newmessage'，'$body'，平台，有效负载：'$body'）；
}
Future getDetails（）异步{
FirebaseDatabase.instance
.reference（）
.儿童（“卖方”）
.child（供应商id）
.一次
.then（（数据快照快照）{
映射值=snapshot.value；
var供应商_id_fr=值['id']；
供应商名称=值['name']；
供应商令牌=值['token']；
//地图数据=地图[‘数据’]；
打印（“名称”+供应商名称）；
打印（“id”+供应商id）；
打印（“代币”+供应商代币）；
});
返回供应商id.toString（）；
}
Future getchat（）异步{
FirebaseDatabase.instance
.reference（）
.child（“聊天”）
.child（小部件。\u订单号）
.一次
.then（（数据快照快照）{
映射值=snapshot.value；
值\uu0.forEach（（键，值）{
映射值_1=值；
chat_id_fr=值_1['chat_id']；
var供应商_msg_fr=值_1['msg']；
var user_id_=value_['user_id']；
var卖方id=价值['卖方id']；
ChatModel ChatModel=new ChatModel.fromJson（值）；
列出消息。添加（聊天室模型）；
list_messages.sort（（x，y）=>x.chat_id_fr.compareTo（y.chat_id_fr））；
});
var list_data=list_messages.toString（）；
打印（list_data.toString（））；
//list_messages=list_messages.reversed.toList（）；
int dfd=列表\消息长度；
对于（int i=0；i curr.chat\u id\u fr>next.chat\u id\u fr？curr:next）；
var value1=列表消息.reduce（（curr，next）=>curr.chat\u id\u fr>next.chat\u id\u fr？curr:next）；
*/
如果（列出消息）
.elementAt（dfd）
.
Future<String> getchat() async {

    FirebaseDatabase.instance
        .reference()
        .child("chat")
        .child(widget._orderNo)
        .onValue
        .listen((list_messages) {})
        .onData((Event event) {
        setState(() {
          if (event.snapshot != null) {
            Map<dynamic, dynamic> mapOfMaps = Map.from(event.snapshot.value);

            list_messages.clear();

            mapOfMaps.values.forEach((value) async {
              ChatModel vendor = ChatModel.fromJson(Map.from(value));
                list_messages.add(vendor);
                list_messages.sort((x, y) => x.chat_id_fr.compareTo(y.chat_id_fr));
          });
        }

      });

      var list_data = list_messages.toString();

      print(list_data.toString());
      // list_messages=list_messages.reversed.toList();

      int dfd = list_messages.length;

      for (int i = 0; i <= list_messages.length; i++) {
        dfd = dfd - 1;

        /*  var value = list_messages.reduce((curr, next) => curr.chat_id_fr > next.chat_id_fr ? curr : next);
        var value1 = list_messages.reduce((curr, next) => curr.chat_id_fr > next.chat_id_fr ? curr : next);
*/

        if (list_messages
            .elementAt(dfd)
            .for_value
            .toString()
            .contains("user")) {
          setState(() {
            ChatMessage message = new ChatMessage(
                text: list_messages.elementAt(dfd).msg,
                vendor: "user",
                vendor_name: vendor_name);
            _messages.add(message);
          });
        } else {
          setState(() {
            ChatMessage message = new ChatMessage(
              text: list_messages.elementAt(dfd).msg.toString(),
              vendor: "vendor",
              vendor_name: vendor_name,
            );
            _messages.add(message);
            //list_messages.reversed.toList();
          });
        }
      }
    });

    return vendor_id.toString();
  }


  FirebaseDatabase.instance
    .reference()
    .child("vendor")
    .child(vendor_id)
    .onValue
    .listen(() {})
    .onData((Event event) {
  setState(() {
    if (event.snapshot != null) {
      print("data= " + event.snapshot.value.toString());

      Map<dynamic, dynamic> mapOfMaps = Map.from(event.snapshot.value);

      arrCategories.clear();

      mapOfMaps.values.forEach((value) async {
        Category category = Category.fromJson(Map.from(value));

        arrCategories.add(category);
      });
    }
  });
});