sticky_and_expandable_list

sticky_and_expandable_list

Flutter implementation of sticky headers and expandable list.Support use it in a CustomScrollView.

README i18n:中文说明

Features

• Build a grouped list, which support expand/collapse section and sticky header.
• Use it with CustomScrollView、SliverAppBar.
• Listen the scroll offset of current sticky header, current sticky header index and switching header index.
• Only use one list widget, so it supports large data and a normal memory usage.
• More section customization support, you can return a new section widget by sectionBuilder, to customize background，expand/collapse animation, section layout, and so on.
• Support add divider.
• Support overlap content.
• Support scroll to index like ListView, by scroll-to-index.
• Pull to refresh and load more, by pull_to_refresh.

Getting Started

In the pubspec.yaml of your flutter project, add the following dependency:

dependencies:
  sticky_and_expandable_list: ^1.1.3

Basic Usage

sectionList is a custom data source for ExpandableListView. We should create a model list to store the information of each section, the model must implement ExpandableListSection.

    //In this example, we create a custom model class(ExampleSection).
    //class ExampleSection implements ExpandableListSection<String> {}
    //so: SliverExpandableChildDelegate<String, ExampleSection>()
    List<ExampleSection> sectionList = List<ExampleSection>();
    return ExpandableListView(
      builder: SliverExpandableChildDelegate<String, ExampleSection>(
          sectionList: sectionList,
          headerBuilder: (context, sectionIndex, index) =>
              Text("Header #$sectionIndex"),
          itemBuilder: (context, sectionIndex, itemIndex, index) {
            String item = sectionList[sectionIndex].items[itemIndex];
            return ListTile(
              leading: CircleAvatar(
                child: Text("$index"),
              ),
              title: Text(item),
            );
          }),
    );

Detail Examples

If you want to use it with sliver widget, use SliverExpandableList instead of ExpandableListView.

FAQ

How to expand/collapse item?

setState(() {
  sectionList[i].setSectionExpanded(true);
});

Example

How to listen current sticky header or the sticky header scroll offset?

  @override
  Widget build(BuildContext context) {
    ExpandableListView(
      builder: SliverExpandableChildDelegate<String, ExampleSection>(
        headerController: _getHeaderController(),
      ),
    )
  }

  _getHeaderController() {
    var controller = ExpandableListController();
    controller.addListener(() {
      print("switchingSectionIndex:${controller.switchingSectionIndex}, stickySectionIndex:" +
          "${controller.stickySectionIndex},scrollPercent:${controller.percent}");
    });
    return controller;
  }

How to set background for each section?

Use sectionBuilder

Customize expand/collapse animation support?

Example

Change Log

CHANGELOG