Я пытаюсь загрузить больше данных, когда дохожу до конца построителя потока, каждый раз, когда я дохожу до конца, построитель потоков перезагружается и возвращается к началу, и он не позволяет мне прокручивать вниз ( продолжайте перезагружать и возвращайтесь к вершина).
Что я пробовал, так это то, что как только я дойду до конца, увеличьте лимит из firebase, но я не уверен, в чем проблема ... кто-нибудь может мне помочь с этим?
Вот пример кода того, что я хочу сделать
_onEndScroll(ScrollMetrics metrics) {
//loadToTrue();
setState(() {
documentLimit = documentLimit + 10;
});
}
StreamBuilder(
initialData: cache,
stream: FirebaseFirestore.instance
.collection("timeline")
.doc(widget.currentUser.id)
.collection('timelinePosts')
.orderBy('timestamp', descending: true)
.limit(documentLimit)
.snapshots(),
builder: (BuildContext context,
AsyncSnapshot<QuerySnapshot> streamSnapshot) {
items = streamSnapshot.data != null &&
streamSnapshot.data.docs != null
? streamSnapshot.data.docs
: [];
List<Post> posts =
items.map((doc) => Post.fromDocument(doc)).toList();
cache = streamSnapshot.data;
return !streamSnapshot.hasData ||
streamSnapshot.connectionState ==
ConnectionState.waiting
? Center(
child: CircularProgressIndicator(),
)
: NotificationListener<ScrollNotification>(
onNotification: (scrollNotification) {
if (scrollNotification is ScrollEndNotification) {
_onEndScroll(scrollNotification.metrics);
}
},
child: Container(
height: MediaQuery.of(context).size.height - 200,
margin: EdgeInsets.only(bottom: 1),
child: ListView.builder(
physics: BouncingScrollPhysics(
parent: ScrollPhysics()),
shrinkWrap: true,
itemCount: items.length,
itemBuilder: (_, i) =>
timelineDecision == "follow"
? posts[i]
: postsLocal[i])));
})
и это код для всех
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import 'package:fluttershare/pages/home.dart';
import 'package:fluttershare/models/user.dart';
import 'package:fluttershare/pages/search.dart';
import 'package:fluttershare/pages/upload.dart';
import 'package:fluttershare/pages/upload_limit.dart';
import 'package:fluttershare/widgets/post.dart';
import 'package:latlong/latlong.dart';
final usersRef = FirebaseFirestore.instance.collection('users');
class Timeline extends StatefulWidget {
final User currentUser;
Timeline({this.currentUser});
@override
_TimelineState createState() => _TimelineState();
}
class _TimelineState extends State<Timeline> {
QuerySnapshot cache;
List<Post> posts;
List<Post> postsLocal;
List<DocumentSnapshot> items;
List<String> followingList = [];
String timelineDecision = "local";
String address = "Norman";
ScrollController listScrollController;
int documentLimit = 5;
void initState() {
super.initState();
getFollowing();
}
getFollowing() async {
QuerySnapshot snapshot = await followingRef
.doc(currentUser.id)
.collection('userFollowing')
.get();
if (mounted) {
setState(() {
followingList = snapshot.docs.map((doc) => doc.id).toList();
});
}
}
setTimeline(String timelineDecision) {
setState(() {
this.timelineDecision = timelineDecision;
});
}
buildToggleTimeline() {
return Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
TextButton(
onPressed: () => setTimeline("follow"),
child: Text('Following',
style: TextStyle(
color: timelineDecision == 'follow'
? Theme.of(context).primaryColor
: Colors.grey)),
style: TextButton.styleFrom(
textStyle: const TextStyle(fontSize: 20),
),
),
TextButton(
onPressed: () => setTimeline("local"),
child: Text('Local',
style: TextStyle(
color: timelineDecision == 'local'
? Theme.of(context).primaryColor
: Colors.grey)),
style: TextButton.styleFrom(
textStyle: const TextStyle(fontSize: 20),
)),
],
);
}
_onEndScroll(ScrollMetrics metrics) {
//loadToTrue();
setState(() {
documentLimit = documentLimit + 10;
});
}
@override
Widget build(context) {
return Scaffold(
appBar: AppBar(
centerTitle: true,
title: const Text('Entango'),
actions: <Widget>[
PopupMenuButton(
icon: const Icon(Icons.add),
onSelected: choiceAction,
itemBuilder: (context) => [
PopupMenuItem(
child: Text("Timelimit post"),
value: 1,
),
PopupMenuItem(
child: Text("Normal post"),
value: 2,
)
]),
IconButton(
icon: const Icon(Icons.search),
tooltip: 'Show Snackbar',
onPressed: () => Navigator.push(
context, MaterialPageRoute(builder: (context) => Search())),
)
],
),
body: ListView(
children: <Widget>[
buildToggleTimeline(),
Divider(
height: 0.0,
),
//buildSlider(),
StreamBuilder(
initialData: cache,
stream: timelineDecision == "follow"
? FirebaseFirestore.instance
.collection("timeline")
.doc(widget.currentUser.id)
.collection('timelinePosts')
.orderBy('timestamp', descending: true)
.limit(documentLimit)
.snapshots()
: FirebaseFirestore.instance
.collection("postsLocalRef")
.doc(address)
.collection("userPosts")
.orderBy('timestamp', descending: true)
.limit(documentLimit)
.snapshots(),
builder: (BuildContext context,
AsyncSnapshot<QuerySnapshot> streamSnapshot) {
items = streamSnapshot.data != null &&
streamSnapshot.data.docs != null
? streamSnapshot.data.docs
: [];
List<Post> posts =
items.map((doc) => Post.fromDocument(doc)).toList();
List<Post> postsLocal =
items.map((doc) => Post.fromDocument(doc)).toList();
cache = streamSnapshot.data;
return !streamSnapshot.hasData ||
streamSnapshot.connectionState ==
ConnectionState.waiting
? Center(
child: CircularProgressIndicator(),
)
: NotificationListener<ScrollNotification>(
onNotification: (scrollNotification) {
if (scrollNotification is ScrollEndNotification) {
_onEndScroll(scrollNotification.metrics);
}
},
child: Container(
height: MediaQuery.of(context).size.height - 200,
margin: EdgeInsets.only(bottom: 1),
child: ListView.builder(
physics: BouncingScrollPhysics(
parent: ScrollPhysics()),
shrinkWrap: true,
itemCount: items.length,
itemBuilder: (_, i) =>
timelineDecision == "follow"
? posts[i]
: postsLocal[i])));
})
],
),
);
}
void choiceAction(int value) {
if (value == 1) {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Upload_limit(
currentUser: currentUser,
)));
} else {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Upload(
currentUser: currentUser,
)));
}
}
}