最新文档未在 Firestore 中列出

Question

我目前正在使用 flutter 做一个聊天应用程序。 我有 2 个用户，当一个用户开始与其他用户聊天时，将在“聊天”集合中添加一个文档。 如果“用户 1”开始聊天，将在集合中添加一个唯一 ID 的文档。 但问题是，当我使用.get() 方法时，该文档没有列出...请检查是什么问题...

这是我的代码：

    import 'dart:async';
    import 'package:cloud_firestore/cloud_firestore.dart';
    import 'package:flutter/material.dart';
    import 'package:flutter/scheduler.dart';
    import 'package:nebula_chat_app/backend/pics.dart';
    import 'package:nebula_chat_app/main.dart';
    import 'package:flutter_svg/flutter_svg.dart';
    import 'package:nebula_chat_app/backend/FireBase.dart';
    class InChat extends StatefulWidget {
      final String secondUserId;
      final String SeconduserName;
    
      const InChat({Key key, this.secondUserId,this.SeconduserName}) : super(key: key);
      @override
      _InChatState createState() => _InChatState(secondUserId,SeconduserName);
    }
    
    class _InChatState extends State {
      var messages;
      String docu;
      List ko;
      Future> offlinemessage;
      final String SecondUserId;
      final String SeconduserName;
      String typeMessage;
      ScrollController _controller2;
      TextEditingController controller2;
    
      _InChatState(this.SecondUserId,this.SeconduserName);
    
      @override
      void initState() {
        controller2 = TextEditingController();
        addUser();
        _controller2 = ScrollController();
        database.collection("Chats").get().then((value) {
          var usersinChat = value.docs.map((e) => e.id).toList();
          print(usersinChat);
          docu = usersinChat.singleWhere((element) => ((element == auth.currentUser.uid.toString() + SecondUserId) || (element == SecondUserId + auth.currentUser.uid.toString())),orElse: ()
            => auth.currentUser.uid.toString() + SecondUserId
          );
         
        }).then((value) {
          messages = database.collection("Chats").doc(docu).collection("Messages").snapshots();
          print("_________________$docu");
        });
        super.initState();
     
      }
      @override
      Widget build(BuildContext context) {
        return Scaffold(
          appBar: AppBar(
            leading: IconButton(icon: Icon(Icons.arrow_back_ios_sharp,color: Colors.white,), onPressed: () => Navigator.pop(context)),
            title: Text(SeconduserName,style: TextStyle(
                fontWeight: FontWeight.w600,
                fontSize: GFS(25, context),
                color: Colors.white
            ),),
            actions: [
              IconButton(icon: Icon(Icons.search,color: Colors.white,), onPressed: null)
            ],
          ),
          body: Container(
            height: MediaQuery.of(context).size.height,
            width: MediaQuery.of(context).size.width,
            color: Theme.of(context).primaryColorLight,
            child: SingleChildScrollView(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Container(
                    height: MediaQuery.of(context).size.height*0.75,
                    width: MediaQuery.of(context).size.width,
                    child: StreamBuilder(
                      stream: messages,
                      builder: (context, snapshot){
                        if(!snapshot.hasData) return Center(child: CircularProgressIndicator(),);
                        else
                          return ListView.builder(
                            controller: _controller2,
                              itemCount: snapshot.data.docs.length,
                              itemBuilder: (context,int index) {
    
                            if (!snapshot.hasData) return SizedBox();
                            else {
                              if (snapshot.data.docs[index]["from"] == SecondUserId){
                                print("Second ======> $SecondUserId");
                                if(_keyboardIsVisible()){
                                  SchedulerBinding.instance.addPostFrameCallback((timeStamp) {_controller2.animateTo(_controller2.position.maxScrollExtent,duration: Duration(milliseconds: 500), curve: Curves.fastOutSlowIn ); });
                                }
                                return ReceiveContainer(
                                    text: snapshot.data.docs[index]["message"].toString());
                              }
                              else{
                                return SendContainer(
                                  text: snapshot.data.docs[index]["message"].toString(), status: "seen",);
                              }
    
                            }
                          }
                          );
                        },
                    )
                  ),
                  Container(
                    height: MediaQuery.of(context).size.height*0.1,
                    width: MediaQuery.of(context).size.width,
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                      children: [
                        Container(
                          height: MediaQuery.of(context).size.height*0.07,
                          alignment: Alignment.center,
                          width: MediaQuery.of(context).size.width*0.75,
                          decoration: BoxDecoration(
                            color: Theme.of(context).cardColor,
                            boxShadow: [BoxShadow(color: Colors.black26,spreadRadius: 1.0,blurRadius: 3.0)],
                            borderRadius: BorderRadius.circular(40.0)
                          ),
                          child: Padding(
                            padding: EdgeInsets.only(left:MediaQuery.of(context).size.width*0.07),
                            child: TextField(
                              controller: controller2,
                              style: TextStyle(
                                color: Colors.black,
                              ),
    
                              decoration: InputDecoration(
                                  focusColor: Colors.black,
                                  hintText: 'Type here',
                                  border: InputBorder.none,
                                  focusedBorder: InputBorder.none,
                                  focusedErrorBorder: InputBorder.none,
                                  disabledBorder: InputBorder.none,
                                  enabledBorder: InputBorder.none,
                                  errorBorder: InputBorder.none,
                                  hintStyle: TextStyle(
                                      color: Colors.black26,
                                      fontSize: GFS(20, context)
                                  )
                              ),
                              onSubmitted: (text) {
                                setState(() {
                                  controller2.text = text;
                                });
                              },
    
                            ),
                          ),
                        ),
                        Container(
                          height: MediaQuery.of(context).size.height*0.07,
                          width: MediaQuery.of(context).size.width*0.2,
                          alignment: Alignment.center,
                          decoration: BoxDecoration(
                              color: Theme.of(context).cardColor,
                              shape: BoxShape.circle,
                              boxShadow: [BoxShadow(color: Colors.black26,spreadRadius: 1.0,blurRadius: 3.0)],
    
                          ),
    
                          child: InkWell(
                            onTap: () {
                              database.collection("Chats").doc(docu).collection("Messages").doc(Timestamp.now().millisecondsSinceEpoch.toString()).set(
                                  {
                                    "from":auth.currentUser.uid.toString(),
                                    "message": controller2.text,
                                    "timestamp" : Timestamp.now().millisecondsSinceEpoch
    
                                  });
                              setState(() {
                                controller2.text = "";
                              });
                              SchedulerBinding.instance.addPostFrameCallback((timeStamp) {_controller2.animateTo(_controller2.position.maxScrollExtent,duration: Duration(milliseconds: 500), curve: Curves.fastOutSlowIn ); });
                            },
                            child: SizedBox(
                                width:MediaQuery.of(context).size.width*0.1,
                                height:MediaQuery.of(context).size.height*0.035,
                                child: SvgPicture.asset(sendIcon,fit: BoxFit.contain,)),
                          ),
                        )
                      ],
                    ),
                  )  ///Typing Container
                ],
              ),
            ),
          ),
        );
      }
      bool _keyboardIsVisible() {
        return !(MediaQuery.of(context).viewInsets.bottom == 0.0);
      }
      void checkCommon() {
      
      }
    }
    
    class ReceiveContainer extends StatelessWidget {
      final String text;
      const ReceiveContainer({Key key, this.text}) : super(key: key);
      @override
      Widget build(BuildContext context) {
        return Container(
          width: MediaQuery.of(context).size.width,
          alignment: Alignment.centerLeft,
          constraints: BoxConstraints(
            minHeight: MediaQuery.of(context).size.height*0.1,
          ),
          child: Padding(
            padding: EdgeInsets.symmetric(vertical: MediaQuery.of(context).size.height*0.02,horizontal:MediaQuery.of(context).size.width*0.05 ),
            child: Container(
              constraints: BoxConstraints(
                minWidth: MediaQuery.of(context).size.width*0.1,
                maxWidth: MediaQuery.of(context).size.width*0.5,
                minHeight: MediaQuery.of(context).size.height*0.06,
              ),
              decoration: BoxDecoration(
                color:Theme.of(context).cardColor,
                borderRadius: BorderRadius.circular(20.0),
                boxShadow: [BoxShadow(color: Colors.black26,spreadRadius: 1.0,blurRadius: 2.0)]
              ),
              child: Padding(
                padding: EdgeInsets.all(MediaQuery.of(context).size.width*0.4*0.1),
                child: Text(text,style: TextStyle(
                    fontWeight: FontWeight.w600,
                    fontSize: GFS(19, context),
                    color:Theme.of(context).textTheme.headline1.color
                ),),
              ),
    
            ),
          ),
        );
      }
    }
    class SendContainer extends StatelessWidget {
      final String text;
      final String status;
      const SendContainer({Key key, this.text,this.status}) : super(key: key);
      @override
      Widget build(BuildContext context) {
        return Container(
          width: MediaQuery.of(context).size.width,
          constraints: BoxConstraints(
            minHeight: MediaQuery.of(context).size.height*0.1,
          ),
          child: Container(
            child: Row(
              mainAxisAlignment: MainAxisAlignment.end,
              children: [
                Container(
                  height: MediaQuery.of(context).size.height*0.03,
                  width: MediaQuery.of(context).size.width*0.1,
                  child: checkStatus(status)
                ),
                Padding(
                  padding: EdgeInsets.only(top: MediaQuery.of(context).size.height*0.02,bottom: MediaQuery.of(context).size.height*0.02,left:MediaQuery.of(context).size.width*0.05 ,right:MediaQuery.of(context).size.width*0.02  ),
                  child: Container(
                    constraints: BoxConstraints(
                      minWidth: MediaQuery.of(context).size.width*0.1,
                      maxWidth: MediaQuery.of(context).size.width*0.5,
                      minHeight: MediaQuery.of(context).size.height*0.06,
                    ),
                    decoration: BoxDecoration(
                        color:Theme.of(context).primaryColorDark,
                        borderRadius: BorderRadius.circular(20.0),
                        boxShadow: [BoxShadow(color: Colors.black26,spreadRadius: 1.0,blurRadius: 2.0)]
    
                    ),
                    child: Padding(
                      padding: EdgeInsets.all(MediaQuery.of(context).size.width*0.4*0.1),
                      child: Text(text,style: TextStyle(
                          fontWeight: FontWeight.w600,
                          fontSize: GFS(19, context),
                          color: Colors.white
                      ),),
                    ),
    
                  ),
                ),
              ],
            ),
          ),
        );
      }
      checkStatus(statusss) {
        {
          if(statusss == 'delivered') return SvgPicture.asset(doubleCheckIcon,fit: BoxFit.contain,color: Colors.black,);
          else if (statusss == 'Not delivered')  return SvgPicture.asset(checkIcon,fit: BoxFit.contain,color: Colors.black,);
          else if (statusss == 'seen') return SvgPicture.asset(doubleCheckIcon,fit: BoxFit.contain,color: Colors.green,);
    
        }
    
      }
    
    }