如何在 flutter 中的项目作为水平滚动而不是垂直列表视图构建器时进行分页？

Question

I have horizontal listview builder so how to make pagination to load more data in case items for horizontal listview !

Answer 1

You can copy paste run full code below
You can use package https://pub.dev/packages/flutter_pagewise

code snippet

return PagewiseListView(
        shrinkWrap: true,
        scrollDirection: Axis.horizontal,
        pageSize: PAGE_SIZE,
        itemBuilder: this._itemBuilder,
        pageFuture: (pageIndex) =>
            BackendService.getPosts(pageIndex * PAGE_SIZE, PAGE_SIZE));

working demo

full code

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_pagewise/flutter_pagewise.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';

class PagewiseListViewExample extends StatelessWidget {
  static const int PAGE_SIZE = 5;

  @override
  Widget build(BuildContext context) {
    return PagewiseListView(
        shrinkWrap: true,
        scrollDirection: Axis.horizontal,
        pageSize: PAGE_SIZE,
        itemBuilder: this._itemBuilder,
        pageFuture: (pageIndex) =>
            BackendService.getPosts(pageIndex * PAGE_SIZE, PAGE_SIZE));
  }

  Widget _itemBuilder(context, PostModel entry, _) {
    return Container(
      width: 200,
      child: ListTile(
        leading: Icon(
          Icons.person,
          color: Colors.brown[200],
        ),
        title: Text(entry.title),
        //subtitle: Text(entry.body),
      ),
    );
  }
}

class BackendService {
  static Future<List<PostModel>> getPosts(offset, limit) async {
    final responseBody = (await http.get(
            'http://jsonplaceholder.typicode.com/posts?_start=$offset&_limit=$limit'))
        .body;

    // The response body is an array of items
    return PostModel.fromJsonList(json.decode(responseBody));
  }

  static Future<List<ImageModel>> getImages(offset, limit) async {
    final responseBody = (await http.get(
            'http://jsonplaceholder.typicode.com/photos?_start=$offset&_limit=$limit'))
        .body;

    // The response body is an array of items.
    return ImageModel.fromJsonList(json.decode(responseBody));
  }
}

class PostModel {
  String title;
  String body;

  PostModel.fromJson(obj) {
    this.title = obj['title'];
    this.body = obj['body'];
  }

  static List<PostModel> fromJsonList(jsonList) {
    return jsonList.map<PostModel>((obj) => PostModel.fromJson(obj)).toList();
  }
}

class ImageModel {
  String title;
  String id;
  String thumbnailUrl;

  ImageModel.fromJson(obj) {
    this.title = obj['title'];
    this.id = obj['id'].toString();
    this.thumbnailUrl = obj['thumbnailUrl'];
  }

  static List<ImageModel> fromJsonList(jsonList) {
    return jsonList.map<ImageModel>((obj) => ImageModel.fromJson(obj)).toList();
  }
}

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Container(height: 200, child: PagewiseListViewExample()),
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}