mo_infinite_scroll

A simple, easy-to-use infinite scroll package for Flutter with minimal required parameters, pull-to-refresh, smart pre-fetching, and full placeholder support.

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Features

• ✅ Minimal required params — just fetcher and itemBuilder
• 🔄 Pull-to-refresh built in (standalone variant)
• ⚡ Pre-fetch the next page before the user reaches the end
• 🛑 Loop prevention — skips fetch when list is too short or already loading
• 📦 Sliver variant — drop into any CustomScrollView, let the parent control refresh
• 🎨 Placeholder widgets — loading, empty, and error states, all overridable
• 🎛️ External controller — trigger refresh() from outside the widget

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Getting started

Add to your pubspec.yaml:

dependencies:
    mo_infinite_scroll: ^1.0.1

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Usage

Standalone list (with pull-to-refresh)

import 'package:mo_infinite_scroll/mo_infinite_scroll.dart';

MoInfiniteScroll<Post>(
  fetcher: (page, limit) => myApi.getPosts(page: page, limit: limit),
  itemBuilder: (context, post) => PostCard(post: post),
)

With all options

MoInfiniteScroll<Post>(
  fetcher: (page, limit) => myApi.getPosts(page: page, limit: limit),
  itemBuilder: (context, post) => PostCard(post: post),
  limit: 20,                          // items per page, passed to your API
  prefetchOffset: 3,                  // pre-fetch when 3 items from the end
  loadingPlaceholder: MyShimmer(),    // first-load skeleton
  emptyPlaceholder: MyEmptyState(),   // zero items
  errorPlaceholder: MyErrorState(),   // fetch error
  loadingMoreIndicator: MySpinner(),  // bottom-of-list spinner
  separatorBuilder: (_, __) => const Divider(),
  padding: const EdgeInsets.all(16),
)

External controller (refresh from an AppBar button)

final _controller = MoInfiniteScrollController<Post>();

// In build():
Scaffold(
  appBar: AppBar(
    actions: [
      IconButton(
        icon: const Icon(Icons.refresh),
        onPressed: () => _controller.refresh(fetcher, limit),
      ),
    ],
  ),
  body: MoInfiniteScroll<Post>(
    controller: _controller,
    fetcher: fetcher,
    itemBuilder: (context, post) => PostCard(post: post),
  ),
)

Sliver variant (inside a CustomScrollView)

final _controller = MoInfiniteScrollController<Post>();

RefreshIndicator(
  onRefresh: () => _controller.refresh(
    (page, limit) => myApi.getPosts(page: page, limit: limit),
    20,
  ),
  child: CustomScrollView(
    slivers: [
      const SliverAppBar(title: Text('Posts'), floating: true),
      MoInfiniteScrollSliver<Post>(
        controller: _controller,
        fetcher: (page, limit) => myApi.getPosts(page: page, limit: limit),
        itemBuilder: (context, post) => PostCard(post: post),
      ),
    ],
  ),
)

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Parameters

Shared by both widgets

Parameter	Type	Required	Default	Description
fetcher	PageFetcher<T>	✅	—	Called for each page. Receives (page, limit). Return [] or fewer items than limit to signal end.
itemBuilder	Widget Function(context, T)	✅	—	Builds a single list item.
limit	int	❌	20	Items per page, forwarded to fetcher.
prefetchOffset	int	❌	3	Start pre-fetching when this many items remain.
controller	MoInfiniteScrollController<T>	❌	internal	External controller to call refresh() from outside.
loadingPlaceholder	Widget	❌	spinner	Shown during the first fetch.
emptyPlaceholder	Widget	❌	inbox icon	Shown when the list is empty.
errorPlaceholder	Widget	❌	error icon + retry	Shown on fetch error.
loadingMoreIndicator	Widget	❌	spinner	Shown at the bottom while loading more.
separatorBuilder	Widget Function(context, index)	❌	none	Optional separator between items.

MoInfiniteScroll only

Parameter	Type	Default	Description
padding	EdgeInsetsGeometry	none	Padding for the internal ListView.
physics	ScrollPhysics	default	Physics for the internal ListView.

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How pre-fetching & loop prevention work

• The next page is fetched when the user scrolls within prefetchOffset items of the end.
• If the current page returned fewer items than limit, hasReachedEnd is set to true and no further fetches are made.
• Concurrent fetches are blocked — if a fetch is already in progress, new calls to fetchNextPage are ignored.
• On error, further fetches are blocked until the user retries.

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License

MIT