用Firebase对Flutter中的数据进行分页

import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';

class PaginationScreen extends StatefulWidget {
  @override
  _PaginationScreenState createState() => _PaginationScreenState();
}

class _PaginationScreenState extends State<PaginationScreen> {
  final FirebaseFirestore _firestore = FirebaseFirestore.instance;
  final int _limit = 10;
  DocumentSnapshot? _lastDocument;
  List<DocumentSnapshot> _documents = [];

  Future<void> _loadData() async {
    QuerySnapshot querySnapshot;
    if (_lastDocument == null) {
      querySnapshot = await _firestore
          .collection('your_collection')
          .orderBy('timestamp', descending: true)
          .limit(_limit)
          .get();
    } else {
      querySnapshot = await _firestore
          .collection('your_collection')
          .orderBy('timestamp', descending: true)
          .startAfterDocument(_lastDocument!)
          .limit(_limit)
          .get();
    }

    if (querySnapshot.docs.isNotEmpty) {
      _lastDocument = querySnapshot.docs.last;
      _documents.addAll(querySnapshot.docs);
    }
  }

  @override
  void initState() {
    super.initState();
    _loadData();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Pagination Example'),
      ),
      body: ListView.builder(
        itemCount: _documents.length,
        itemBuilder: (context, index) {
          final document = _documents[index];
          return ListTile(
            title: Text(document['title']),
            subtitle: Text(document['content']),
          );
        },
        // 触底加载下一页数据
        onEndReached: () {
          _loadData();
        },
      ),
    );
  }
}