/webf-infinite-scrolling

name: webf-infinite-scrolling
description: Create high-performance infinite scrolling lists with pull-to-refresh and load-more capabilities using WebFListView. Use when building feed-style UIs, product catalogs, chat messages, or any scrollable list that needs optimal performance with large datasets.

WebF Infinite Scrolling

> **Note**: WebF development is nearly identical to web development - you use the same tools (Vite, npm, Vitest), same frameworks (React, Vue, Svelte), and same deployment services (Vercel, Netlify). This skill covers **performance optimization for scrolling lists** - a WebF-specific pattern that provides native-level performance automatically.

Build high-performance infinite scrolling lists with Flutter-optimized rendering. WebF's `WebFListView` component automatically handles performance optimizations at the Flutter level, providing smooth 60fps scrolling even with thousands of items.

Why Use WebFListView?

In browsers, long scrolling lists can cause performance issues:

• DOM nodes accumulate (memory consumption)
• Re-renders affect all items (slow updates)
• Intersection observers needed for virtualization
• Complex state management for infinite loading

**WebF's solution**: `WebFListView` delegates rendering to Flutter's optimized ListView widget, which:

• ✅ Automatically virtualizes (recycles) views
• ✅ Maintains 60fps scrolling with thousands of items
• ✅ Provides native pull-to-refresh and load-more
• ✅ Zero configuration - optimization happens automatically

Critical Structure Requirement

**⚠️ IMPORTANT**: For Flutter optimization to work, each list item must be a **direct child** of `WebFListView`:

✅ CORRECT: Direct Children

<WebFListView>
  <div>Item 1</div>
  <div>Item 2</div>
  <div>Item 3</div>
  {/* Each item is a direct child */}
</WebFListView>

❌ WRONG: Wrapped in Container

<WebFListView>
  <div>
    {/* DON'T wrap items in a container div */}
    <div>Item 1</div>
    <div>Item 2</div>
    <div>Item 3</div>
  </div>
</WebFListView>

**Why this matters**: Flutter's ListView requires direct children to perform view recycling. If items are wrapped in a container, Flutter sees only one child (the container) and cannot optimize individual items.

React Setup

Installation

npm install @openwebf/react-core-ui

Basic Scrolling List

import { WebFListView } from '@openwebf/react-core-ui';

function ProductList() {
  const products = [
    { id: 1, name: 'Product 1', price: 19.99 },
    { id: 2, name: 'Product 2', price: 29.99 },
    { id: 3, name: 'Product 3', price: 39.99 },
    // ... hundreds or thousands of items
  ];

  return (
    <WebFListView scrollDirection="vertical" shrinkWrap={true}>
      {products.map(product => (
        // ✅ Each item is a direct child
        <div key={product.id} className="product-card">
          <h3>{product.name}</h3>
          <p>${product.price}</p>
        </div>
      ))}
    </WebFListView>
  );
}

Infinite Scrolling with Load More

import { WebFListView, WebFListViewElement } from '@openwebf/react-core-ui';
import { useRef, useState } from 'react';

function InfiniteList() {
  const listRef = useRef<WebFListViewElement>(null);
  const [items, setItems] = useState([1, 2, 3, 4, 5]);
  const [page, setPage] = useState(1);

  const handleLoadMore = async () => {
    try {
      // Simulate API call
      await new Promise(resolve => setTimeout(resolve, 1000));

      // Fetch next page
      const newItems = Array.from(
        { length: 5 },
        (_, i) => items.length + i + 1
      );

      setItems(prev => [...prev, ...newItems]);
      setPage(prev => prev + 1);

      // Check if there's more data
      const hasMore = page < 10; // Example: 10 pages max

      // Notify WebFListView that loading finished
      listRef.current?.finishLoad(hasMore ? 'success' : 'noMore');
    } catch (error) {
      // Notify failure
      listRef.current?.finishLoad('fail');
    }
  };

  return (
    <WebFListView
      ref={listRef}
      onLoadMore={handleLoadMore}
      scrollDirection="vertical"
      shrinkWrap={true}
    >
      {items.map(item => (
        <div key={item} className="item">
          Item {item}
        </div>
      ))}
    </WebFListView>
  );
}

Pull-to-Refresh

import { WebFListView, WebFListViewElement } from '@openwebf/react-core-ui';
import { useRef, useState } from 'react';

function RefreshableList() {
  const listRef = useRef<WebFListViewElement>(null);
  const [items, setItems] = useState([1, 2, 3, 4, 5]);

  const handleRefresh = async () => {
    try {
      // Simulate API call
      await new Promise(resolve => setTimeout(resolve, 1000));

      // Fetch fresh data
      const freshItems = [1, 2, 3, 4, 5];
      setItems(freshItems);

      // Notify WebFListView that refresh finished
      listRef.current?.finishRefresh('success');
    } catch (error) {
      // Notify failure
      listRef.current?.finishRefresh('fail');
    }
  };

  return (
    <WebFListView
      ref={listRef}
      onRefresh={handleRefresh}
      scrollDirection="vertical"
      shrinkWrap={true}
    >
      {items.map(item => (
        <div key={item} className="item">
          Item {item}
        </div>
      ))}
    </WebFListView>
  );
}

Combined: Pull-to-Refresh + Infinite Scrolling

import { WebFListView, WebFListViewElement } from '@openwebf/react-core-ui';
import { useRef, useState } from 'react';

function FeedList() {
  const listRef = useRef<WebFListViewElement>(null);
  const [posts, setPosts] = useState([
    { id: 1, title: 'Post 1', content: 'Content 1' },
    { id: 2, title: 'Post 2', content: 'Content 2' },
    { id: 3, title: 'Post 3', content: 'Content 3' },
  ]);
  const [page, setPage] = useState(1);

  const handleRefresh = async () => {
    try {
      // Fetch latest posts
      const response = await fetch('/api/posts?page=1');
      const freshPosts = await re