sliver_center 1.1.2

A sliver that centers its child sliver within itself, primarily designed for centering slivers wrapped in SliverConstrainedCrossAxis.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:sliver_center/sliver_center.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Sliver Center Example',
      debugShowCheckedModeBanner: false,
      home: HomeScreen(),
    );
  }
}

class HomeScreen extends StatelessWidget {
  const HomeScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: CustomScrollView(
        slivers: [
          SliverCrossAxisGroup(
            slivers: [
              SliverCrossAxisExpanded(
                flex: 1,
                sliver: SliverCenter(
                  sliver: SliverConstrainedCrossAxis(
                    maxExtent: 100,
                    sliver: SliverList.builder(
                      itemBuilder: (context, index) {
                        final color = index % 2 == 0 ? Colors.red : Colors.blue;
                        return Container(
                          height: 100,
                          width: double.infinity,
                          margin: EdgeInsets.only(
                            bottom: 10,
                          ),
                          color: color,
                          child: TextButton(
                            onPressed: () {},
                            child: Text(
                              'test_$index',
                            ),
                          ),
                        );
                      },
                    ),
                  ),
                ),
              ),
              SliverConstrainedCrossAxis(
                maxExtent: 1,
                sliver: SliverToBoxAdapter(
                  // Add the divider here
                  child: Container(
                    height: 10000, // Height of the divider line
                    color: Colors.grey, // Color of the divider line
                  ),
                ),
              ),
              SliverCrossAxisExpanded(
                flex: 1,
                sliver: SliverLayoutBuilder(
                  builder: (context, constraints) => SliverConstrainedCrossAxis(
                    maxExtent: constraints.crossAxisExtent * 0.5,
                    sliver: SliverCenter(
                      sliver: SliverList.builder(
                        itemBuilder: (context, index) {
                          final color =
                              index % 2 == 0 ? Colors.red : Colors.blue;
                          return Container(
                            height: 100,
                            width: double.infinity,
                            margin: EdgeInsets.only(
                              bottom: 10,
                            ),
                            color: color,
                          );
                        },
                      ),
                    ),
                  ),
                ),
              )
            ],
          ),
        ],
      ),
    );
  }
}