I am trying to fetch user chats from firebase firestore but all I can see on the chat screen is a circular progress indicator, Can anyone help me with that plz?
Future<Stream<QuerySnapshot>> getChatRoomMessages(chatRoomId) async {
return FireStore.collection("ChatRooms")
.doc(chatRoomId)
.collection("chat")
.orderBy("ts", descending: true)
.snapshots();
}
Widget chatMessages() {
return StreamBuilder<QuerySnapshot>(
stream: messageStream,
builder: (context, snapshot) {
return snapshot.hasData
? ListView.builder(
itemCount: snapshot.data?.docs.length,
itemBuilder: (context, index) {
DocumentSnapshot ds =
snapshot.data?.docs[index] as DocumentSnapshot<Object?>;
return Text(ds["message"]);
})
: Center(child: CircularProgressIndicator());
},
);
}
getandSetMessages() async {
messageStream = await getChatRoomMessages(chatRoomID);
setState(() {});
}
#override
void initState() {
getandSetMessages();
super.initState();
}
This is where am implementing it in scaffold body ->
body: Stack(
children: <Widget>[
chatMessages(),
Align(
alignment: Alignment.bottomLeft,
child: Container(
Related
I previously asked a question on how to load new messages with Firebase Realtime Database using infinite scrolling.
Here is the code I currently use to list MessageWidgets in my chat application
This runs when the chat screen opens:
void initState() {
super.initState();
_scrollController.addListener(() {
if (_scrollController.position.atEdge) {
bool isTop = _scrollController.position.pixels == 0;
if (isTop) {
//add more messages
} else {
print('At the bottom');
}
}
});
}
This is the code for the list of messages:
Flexible(
child: StreamBuilder(
stream: FirebaseDatabase.instance
.ref("messages/${widget.placeID}")
.orderByChild("timeStamp")
.limitToLast(20)
.onValue,
builder:
(context, AsyncSnapshot<DatabaseEvent> snapshot) {
if (!snapshot.hasData) {
return const CircularProgressIndicator();
} else {
Map<dynamic, dynamic> map =
snapshot.data!.snapshot.value as dynamic;
List<dynamic> list = [];
list.clear();
list = map.values.toList();
return Align(
alignment: Alignment.bottomCenter,
child: Padding(
padding: const EdgeInsets.only(bottom: 20),
child: ListView.builder(
controller: _scrollController,
// shrinkWrap: true,
itemCount: list.length,
itemBuilder: (context, index) {
final json = list[index]
as Map<dynamic, dynamic>;
final message = Message.fromJson(json);
return MessageWidget(
message: message.text,
id: message.uid,
name: message.name,
lastSender: message.lastSender,
date: message.timeStamp,
profilePicture:
message.profilePicture,
);
}),
),
);
}
},
),
Based on the https://stackoverflow.com/a/74562746/16727709, I am wondering how to load more messages when the user scrolls to the top.
The list initially loads data for this query:
FirebaseDatabase.instance
.ref("messages/${widget.placeID}")
.orderByChild("timeStamp")
.limitToLast(20);
I would like to run this query and update the Listview.builder by adding the results of this query when the user scrolls to the top
FirebaseDatabase.instance
.ref("messages/${widget.placeID}")
.orderByChild("timeStamp")
.endBefore(timeStampValueOfOldestSeenItem, keyOfOldestSeenItem)
.limitToLast(10);
Any help would be appreciated!
I have encountered an error where the data is printed out in terminal but do not display in the application.
Future<DocumentSnapshot> getTeacher() async {
var firebaseUser = await FirebaseAuth.instance.currentUser;
var docRef = FirebaseFirestore.instance.collection("User");
var query = docRef.where("type", isEqualTo: "teacher").limit(10);
query.get().then((QuerySnapshot querySnapshot) {
querySnapshot.docs.forEach((doc) {
print(doc["name"]);
print(doc["email"]);
});
});
}
body: new FutureBuilder(
future: getTeacher(),
builder:
(BuildContext context, AsyncSnapshot<DocumentSnapshot> snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
return ListView.builder(
shrinkWrap: true,
itemCount: 1,
itemBuilder: (BuildContext context, int index) {
return Row(
children: <Widget>[
Expanded(child: Text(snapshot.data["name"])),
Expanded(child: Text(snapshot.data["email"])),
Expanded(
child: IconButton(
icon: Icon(Icons.chat), onPressed: () {}))
],
);
});
}
return Container();
}),
this is the output in the terminal
Your getTeacher()-Function does not return your Future. Because of this
the Nullpointer-Exception ist thrown. You should return query.get() instead of listen to it.
You should also not call getTeacher() in the build-Function because it will be called at every build.
EDIT:
Your method:
Future<DocumentSnapshot> getTeacher() async {
var firebaseUser = await FirebaseAuth.instance.currentUser;
var docRef = FirebaseFirestore.instance.collection("User");
var query = docRef.where("type", isEqualTo: "teacher").limit(1);
return (await query.get()).docs[0];
}
Variable of your widget:
final Future<DocumentSnapshot> teacher = getTeacher();
Your FutureBuilder:
new FutureBuilder(
future: teacher,
builder: ...
)
You are not returning anything from future function. Please check below code
Future<List<DocumentSnapshot>> getTeacher() async {
var firebaseUser = await FirebaseAuth.instance.currentUser;
var docRef = FirebaseFirestore.instance.collection("users");
QuerySnapshot query =
await docRef.where("user_device_language", isEqualTo: "en").limit(10).get();
return query.docs;
}
And handle null value in list view like this
body: new FutureBuilder(
future: getTeacher(),
builder: (BuildContext context, AsyncSnapshot<List<DocumentSnapshot>> snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
if (snapshot.data != null) {
return ListView.builder(
shrinkWrap: true,
itemCount: snapshot.data.length,
itemBuilder: (BuildContext context, int index) {
return Row(
children: <Widget>[
Expanded(child: Text(snapshot.data[index]["name"])),
Expanded(child: Text(snapshot.data[index]["email"])),
Expanded(child: IconButton(icon: Icon(Icons.chat), onPressed: () {}))
],
);
});
} else {
return Text('No Data');
}
}
return Container();
},
),
I am using streambuilder to display snapshot data but it is not displaying. The screen is just blank but When I use the future builder with get() methode it display the data but I want realtime changes. I am new to flutter please help me with this. here is code.
class TalentScreen2 extends StatelessWidget {
final Query _fetchFavUser = FirebaseRepo.instance.fetchFavUsers();
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Column(
children: [
Text('Talent Screen 2(Favourites)'),
Expanded(child: _retrieveData(context))
],
),
),
);
}
Widget _retrieveData(BuildContext context) => StreamBuilder<QuerySnapshot>(
stream: _fetchFavUser.snapshots(),
builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
if (snapshot.hasError) return const Text('Something went wrong');
if (!snapshot.hasData) return const Text('Alas! No data found');
if (snapshot.connectionState == ConnectionState.waiting)
return Center(
child: CircularProgressIndicator(
strokeWidth: 2.0,
));
if (snapshot.connectionState == ConnectionState.done)
return theUserInfo(snapshot.data.docs);
return Container();
});
Widget theUserInfo(List<QueryDocumentSnapshot> data) {
return ListView.builder(
shrinkWrap: true,
itemCount: data.length,
itemBuilder: (BuildContext context, int index) {
var uid = data[index]['uid'];
TalentHireFavModel userData = TalentHireFavModel.fromMap(
data[index].data(),
);
return Card(
child: Column(
children: <Widget>[
Text(data[index]['orderBy']),
// Text(userData.name ?? ''),
Text(userData.categories),
Text(userData.skills),
// Text(userData.country ?? ''),
Text(userData.phoneNo),
Text(userData.hourlyRate),
Text(userData.professionalOverview),
Text(userData.skills),
Text(userData.expert),
// Text(userData.createdAt ?? ''),
_iconButton(userData.uid, context),
],
),
);
});
}
Future<DocumentSnapshot> fetch(data) async =>
await FirebaseRepo.instance.fetchWorkerUserData(data);
Widget _iconButton(uid, context) {
return IconButton(
icon: Icon(Icons.favorite),
onPressed: () {
BlocProvider.of<TalentFavCubit>(context).removeTalentFav(uid);
});
}
}
and here is the firestore query methode where I am just applying simple query to fetch all documents and display them. I want real-time changes
Query fetchFavUsers() {
var data = _firestore
.collection('workerField')
.doc(getCurrentUser().uid)
.collection('favourites')
// .where('uid', isNotEqualTo: getCurrentUser().uid)
.orderBy('orderBy', descending: true);
return data;
}
The solution is to just return the function. Get that method out of if statement and place it in just return statement.
At first, when i started writing my calls to get data from firestore, it worked. But when i tried writing more docs to my collection, it failed to bring data for the docs i recently added. Then, when i deleted the first one i added, i stopped receiveing data from firestore all together. I have tried several methods, but have all ended in failure.
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
class collect extends StatefulWidget {
#override
_collectState createState() => _collectState();
}
class _collectState extends State<collect>
{
Future _data;
void initState()
{
super.initState();
_data = getStuff();
}
Future getStuff()
async {
var firestore = FirebaseFirestore.instance;
QuerySnapshot qn = await firestore.collection("buses").get();
return qn.docs;
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: FutureBuilder(
future: _data,
builder: (_, snapshot)
{
if(snapshot.connectionState == ConnectionState.waiting)
{
return Center(
child:Text("Loading")
);
}
else if(snapshot.connectionState == ConnectionState.done)
{
return ListView.builder(itemCount: snapshot.data.length,itemBuilder:(_, index)
{
return Container(
child: ListTile(
title: Text(snapshot.data[index].data()["name"].toString()),
subtitle: Text(snapshot.data[index].data()["price"].toString()),
),
);
});
}
},
),
);
}
}
```
Define your database call as,
Future getStuff() async {
var docs;
await FirebaseFirestore.instance
.collection("buses")
.get()
.then((querySnapshot) {
docs = querySnapshot.docs;
});
return docs;
}
Then use the FutureBuilder in the build() function as,
return Scaffold(
body: Center(
child: FutureBuilder<dynamic>(
future: getStuff(),
builder: (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
if (snapshot.hasData) {
return ListView.builder(
itemCount: snapshot.data.length,
itemBuilder: (_, index) {
return Container(
child: ListTile(
title: Text(
snapshot.data[index].data()["name"].toString()),
subtitle: Text(
snapshot.data[index].data()["price"].toString()),
),
);
});
} else {
return CircularProgressIndicator();
}
},
),
),
);
I wrapped the FutureBuilder inside a Center just for clarity, you may remove that Center widget.
I have a small problem, I need to retrieve into my list a collection retrieved by StreamBuilder from Firestore.
I am using snapshot.data.documents.lenght but once I add it I got error:
Class 'DocumentSnapshot' has no instance getter 'documents'.
Receiver: Instance of 'DocumentSnapshot'
Tried calling: documents
this is my code:
Stream<DocumentSnapshot> getDatabase() async* {
FirebaseUser user = await FirebaseAuth.instance.currentUser();
yield* Firestore.instance
.collection('dataCollection')
.document(user.uid)
.snapshots();
}
#override
Widget build(BuildContext context,) {
return StreamBuilder(
stream: getDatabase(),
builder: (context, snapshot,) {
if (snapshot.data != null) {
return Column(
children: <Widget>[
Container(
height: 500,
child: ListView.builder(
shrinkWrap: true,
itemCount: 2,
itemBuilder: (BuildContext context, int index) {
return Card(
color: Color(0xFF1f2032),
elevation: 15,
child: Text(
snapshot.data['phone']..
just change your code as following
Stream dataStream
then
#override
void initState() {
getDatabase().then((value) {
dataStream = value;
setState(() {});
});
super.initState();
}
the funcion getDatbase()
getDatabase() async {
FirebaseUser user = await FirebaseAuth.instance.currentUser();
yield* Firestore.instance
.collection('dataCollection')
.document(user.uid)
.snapshots();
}
then
#override
Widget build(BuildContext context,) {
return StreamBuilder(
stream: dataStream,
builder: (context, snapshot,) {
if (snapshot.data != null) {
return Column(
children: <Widget>[
Container(
height: 500,
child: ListView.builder(
shrinkWrap: true,
itemCount: 2,
itemBuilder: (BuildContext context, int index) {
return Card(
color: Color(0xFF1f2032),
elevation: 15,
child: Text(
snapshot.data['phone']..
Try this,
StreamBuilder(
stream: stream,
builder: (BuildContext context,
AsyncSnapshot<List<DocumentSnapshot>> snapshots) {
if (snapshots.connectionState == ConnectionState.active &&
snapshots.hasData) {
return Expanded(
child: ListView.builder(
scrollDirection: Axis.vertical,
shrinkWrap: true,
itemCount: snapshots.data.length,
itemBuilder: (BuildContext context, int index) {
//do something with snapshot.
}
}
return Container();
},
),
);
} else {
return Container();
}
},
),
Initialise your stream like this,
Stream<DocumentSnapshot> stream;
Future<dynamic> getDatabase() async {
FirebaseUser user = await FirebaseAuth.instance.currentUser();
setState(() {
stream=Firestore.instance
.collection('dataCollection')
.document(user.uid)
.snapshots();
});
}
You can call getDatabase() in initState.
Update:-
This is your full code.
class DataCo extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.white,
appBar: AppBar(
backgroundColor: Colors.blue,
),
body: Column(
children: [
CollectData(),
],
),
);
}
}
class CollectData extends StatefulWidget {
#override
_CollectDataState createState() => _CollectDataState();
}
class _CollectDataState extends State<CollectData> {
final String phone;
final String wife;
final String location;
_CollectDataState({this.phone, this.wife, this.location});
#override
void initState() {
super.initState();
getDatabase();
}
Stream<DocumentSnapshot> stream;
Future<dynamic> getDatabase() async {
FirebaseUser user = await FirebaseAuth.instance.currentUser();
setState(() {
stream=Firestore.instance
.collection('dataCollection')
.document(user.uid)
.snapshots();
});
}
#override
Widget build(BuildContext context,) {
return StreamBuilder(
stream: stream,
builder: (BuildContext context,
AsyncSnapshot<DocumentSnapshot> snapshots) {
if (snapshots.connectionState == ConnectionState.active &&
snapshots.hasData) {
return Expanded(
child: ListView.builder(
scrollDirection: Axis.vertical,
shrinkWrap: true,
itemCount: snapshots.data.length,
itemBuilder: (BuildContext context, int index) {
//do something with snapshot.
}
}
return Container();
},
),
);
} else {
return Container();
}
},
);
}
}
class NoData extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Column(
children: [
Text('No Data available'),
],
);
}
}