quirijngb / lazy-load-scrollview Goto Github PK

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:http/http.dart';
import 'package:lazy_load_scrollview/lazy_load_scrollview.dart';

main() {
  runApp(MaterialApp(
    home: Scaffold(
      appBar: AppBar(
        title: Text('LazyLoading'),
      ),
      body: Home(),
    ),
  ));
}

class Home extends StatefulWidget {
  final int pageSize;

  Home({this.pageSize = 10});

  @override
  State<StatefulWidget> createState() => HomeState();
}

class HomeState extends State<Home> {
  List<Map> documents;
  bool loading;
  int currentPage;
  Client client;

  @override
  void initState() {
    super.initState();
    documents = [];
    loading = false;
    currentPage = 0;
    client = Client();
    () async {
      await _loadMore();
    }();
  }

// 'http://monster6.disco.unimib.it/API/documents/search/?s=informatica&paging=${widget.pageSize}&offset=${currentPage > 0 ? currentPage * widget.pageSize : ''}'
  Future<void> _loadMore() async {
    print('loading more!');
    setState(() {
      loading = true;
    });
    final response = await client.get(
      Uri.http(
        'monster6.disco.unimib.it',
        '/API/documents/search',
        {
          's': 'informatica',
          'paging': '${widget.pageSize}',
          'offset':
              currentPage > 0 ? '${currentPage * widget.pageSize + 1}' : null
        },
      ),
    );
    print(jsonDecode(response.body));
    final results = List<Map>.from(
        jsonDecode(response.body)['documentsAleph']['documents']);
    if (mounted) {
      setState(() {
        loading = false;
        documents.addAll(results);
        currentPage++;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: <Widget>[
        Positioned.fill(
          child: LazyLoadScrollView(
            child: ListView.builder(
              itemCount: documents.length,
              itemBuilder: (context, index) {
                return AspectRatio(
                  aspectRatio: 2,
                  child: Card(
                    child: Text(documents[index]['title'] ?? 'null'),
                  ),
                );
              },
            ),
            onEndOfPage: () {
              _loadMore();
            },
            scrollOffset: 600,
          ),
        ),
        Positioned(
          top: 0,
          left: 0,
          right: 0,
          child: loading ? LinearProgressIndicator() : Container(),
        ),
      ],
    );
  }
}

LazyLoadScrollView(
onEndOfPage: ( ) { }
child: SingleChildScrollView(      //vertical scroll view

child : Column( 
. . . . . 
CarouselSlider (                         //horizontalScrollview
. . . . . 
),
),);

.
.
.
.
// rest of the code

            return LazyLoadScrollView(
              onEndOfPage: () {
                BlocProvider.of<FetchProductsBloc>(context).add(
                  FetchProducts(count: 20),
                );
              },
              child: ListView.builder(
                itemCount: state.count,
                itemBuilder: (context, index) {
                  return ListTile(
                    title: Text('Loaded Data $index'),
                  );
                },
              ),
            );
.
.
.
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