flutter_long_list

A Flutter LongList with Provider which supports ListView, GridView and Slivers

Features

1. Support refresh & loadmore & error

2. Use Provider4.x to manage list data, and use Selector can improve performanc

3. Support ListView, GridView and Slivers

4. Easy api, custom loading & nomore style

5. Support List item exposure listener

6. Support ScrollToIndex

Get started

Add it to your pubspec.yaml file:

  dependencies:
     flutter_long_list: 0.1.6

Install packages from the command line

  flutter packages get

If you like this package, consider supporting it by giving it a star on Github and a like on pub.dev ❤️

Basic Usage

Create a GridView By flutter_long_list

Step1 - Use ChangeNotifierProvider

 ChangeNotifierProvider<LongListProvider<T>>(
   create: (_) => LongListProvider<T>(),
   child: GridViewDemo(),
 );

Step2 - Init LongListProvider

·param id: list custom id is required.

·param pageSize: list load more need pagesize to request.

·param request: list load more function, offset = page * pageSize(page initialValue = 0).

@override
initState() {
  longListProvider.init(
    id: id,
    pageSize: 5,
    request: (int offset) async => await _getList(offset),
  );
  // your code...
}
// 'list' & 'total' & 'error' can not be modified. These field will use to loadmore.
Future<LongListData> _getList(int offset) async{
  final result = await api(0, 10);
  if (result['list'] != null) {
    return LongListData(
      list: result['list'],
      total: result['total']
    );
  } else {
    return LongListData(error: 'error');
  }
}

Step3 - Use LongList

·param id: list custom id you have inited.

·param gridDelegate: gridView property.

·param mode: enum LongListMode {list, grid, sliver_list, sliver_grid}

·param itemWidget: (BuildContext context, LongListProvider<T> provider, String id, int index, T data) { return your custom widget }

LongList<T>(
  id: id,
  gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
    crossAxisCount: 2,
    crossAxisSpacing: 10.0,
    mainAxisSpacing: 10.0,
  ),
  padding: EdgeInsets.only(left: 10, right: 10),
  mode: LongListMode.grid,
  itemWidget: itemWidget,
)

Then you have finished to create a LongList GridView Widget easily!

Feature Use

1. You can use it to make your list data shared. Need to be determined the list has inited before use these functions. Please see ListView example

prvider.addItem(id, index, data); // add item
prvider.addItems(id, data); // add list
prvider.changeItem(id, index, data); // delete item
prvider.removeItem(id, index); // remove item

• your data must have clone method, because provider Selector need.

2. If you want use exposure listener, only add exposureCallback

LongList<T>(
  id: id,
  gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
    crossAxisCount: 2,
    crossAxisSpacing: 10.0,
    mainAxisSpacing: 10.0,
  ),
  padding: EdgeInsets.only(left: 10, right: 10),
  mode: LongListMode.grid,
  itemWidget: itemWidget,
  exposureCallback: (LongListProvider<T> provider, List<ToExposureItem> exposureList) {
    exposureList.forEach((item) {
      print('上报数据：${provider.list[item.index]} ${item.index} ${item.time}');
    });
  },
)

if use sliver mode, please must add 'sliverHeadHeight' param. It equals your sliverHead's expandedHeight.

3. Use ScrollToIndex

ScrollToIndexController scrollController = ScrollToIndexController();
scrollController.scrollToIndex(LongListProvider provider, String id, int index);