Grouped list package for Flutter.

A flutter ListView in which list items can be grouped to sections.

Features

Sound null safety support!
Easy creation of chat dialog.
List Items can be separated in groups.
For the groups an individual header can be set.
Almost all fields from ListView.builder available.

Getting Started

Add the package to your pubspec.yaml:

 grouped_list: ^5.1.3

In your dart file, import the library:

import 'package:grouped_list/grouped_list.dart';

Instead of using a ListView create a GroupedListView Widget:

 GroupedListView<dynamic, String>(
   elements: _elements,
   groupBy: (element) => element['group'],
   groupSeparatorBuilder: (String groupByValue) => Text(groupByValue),
   itemBuilder: (context, dynamic element) => Text(element['name']),
   itemComparator: (item1, item2) => item1['name'].compareTo(item2['name']), // optional
   useStickyGroupSeparators: true, // optional
   floatingHeader: true, // optional
   order: GroupedListOrder.ASC, // optional
   footer: Text("Widget at the bottom of list"), // optional
 ),

Parameters:

Name	Description	Required	Default value
`elements`	A list of the data you want to display in the list	required	-
`groupBy`	Function which maps an element to its grouped value	required	-
`itemBuilder` / `indexedItemBuilder` / `interdependentItemBuilder`	Function which returns an Widget which defines the item. `indexedItemBuilder` provides the current index as well. `interdependentItemBuilder` provides the previous and next items as well.`indexedItemBuilder` is preferred over `interdependentItemBuilder` and `interdependentItemBuilder` is preferred over`itemBuilder`	yes, either of them	-
`groupSeparatorBuilder` / `groupHeaderBuilder`	Function which returns a Widget which defines the group headers. While `groupSeparatorBuilder` gets the `groupBy`-value as parameter `groupHeaderBuilder` gets the whole element. If both are defined `groupHeaderBuilder` is preferred	yes, either of them	-
`groupStickyHeaderBuilder`	Function which returns a Widget which defines the sticky group header, when `useStickyGroupSeparators` is `true`. If not defined `groupSeparatorBuilder` or `groupHeaderBuilder` will be used as described above.	no	-
`useStickyGroupSeparators`	When set to true the group header of the current visible group will stick on top	no	`false`
`floatingHeader`	Whether the sticky group header float over the list or occupy it's own space	no	`false`
`stickyHeaderBackgroundColor`	Defines the background color of the sticky header. Will only be used if `useStickyGroupSeparators` is used	no	`Color(0xffF7F7F7)`
`separator`	A Widget which defines a separator between items inside a group	no	no separator
`groupComparator`	Can be used to define a custom sorting for the groups. Otherwise the natural sorting order is used	no	-
`itemComparator`	Can be used to define a custom sorting for the elements inside each group. Otherwise the natural sorting order is used	no	-
`order`	Change to `GroupedListOrder.DESC` to reverse the group sorting	no	`GroupedListOrder.ASC`
`footer`	Widget at the bottom of the list	no	-

Also the fields from ListView.builder can be used.

Highlight - SilverGroupedList

Now supporting a grouped list based on a silver list. Just use SilverGroupedListView instead of GroupedListView. An example can be found under example/lib/example_silver. Note that some options of the GroupedListView are currently not available in SilverGroupedListView.

Highlight - Chat Dialog

Easy creation of chat dialogs. Just set the option reverse to true and order to GroupedListOrder.DESC. A full example can be found in the examples. The list will be scrolled to the end in the initial state and therefore scrolling will be against redeaing direction.

My other packages :

For easy creation of chat-like dialogs:

Check out my other package StickyGroupedList, which is based on the scrollable_positioned_list.