Row Expanding Grid View Thingy - by Simon Lightfoot - Humpday Q&A :: 28th February 2024 #Flutter #Dart - https://www.youtube.com/watch?v=m1ytM8iBGHY

humpday_280224-1.dart

// MIT License
//
// Copyright (c) 2023 Simon Lightfoot
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
import 'dart:math';

import 'package:flutter/material.dart';

void main() {
  runApp(const MaterialApp(home: Home()));
}

class Home extends StatefulWidget {
  const Home({super.key});

  @override
  State<Home> createState() => _HomeState();
}

class _HomeState extends State<Home> {
  final _data = <double>[
    50, 100, 75, //
    10, 150, 25, //
    80, 45, 42, //
    42, 123 //
  ];

  @override
  Widget build(BuildContext context) {
    return Material(
      child: ExpandingRowGrid(
        crossAxisCount: 3,
        itemCount: _data.length,
        itemBuilder: (BuildContext context, int index) {
          return ItemBox(_data[index]);
        },
      ),
    );
  }
}

class ExpandingRowGrid extends StatelessWidget {
  const ExpandingRowGrid({
    super.key,
    required this.crossAxisCount,
    required this.itemCount,
    required this.itemBuilder,
  });

  final int crossAxisCount;
  final int itemCount;
  final IndexedWidgetBuilder itemBuilder;

  @override
  Widget build(BuildContext context) {
    return CustomScrollView(
      slivers: [
        for (var i = 0; i < itemCount; i += crossAxisCount) //
          SliverRowGroup(
            children: [
              for (int j = i; j < i + crossAxisCount; j++) //
                if (j < min(i + crossAxisCount, itemCount))
                  itemBuilder(context, j)
                else
                  const SizedBox(),
            ],
          ),
      ],
    );
  }
}

class SliverRowGroup extends StatelessWidget {
  const SliverRowGroup({
    super.key,
    required this.children,
  });

  final List<Widget> children;

  @override
  Widget build(BuildContext context) {
    return SliverToBoxAdapter(
      child: IntrinsicHeight(
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            for (final child in children) //
              Expanded(child: child),
          ],
        ),
      ),
    );
  }
}

class ItemBox extends StatelessWidget {
  const ItemBox(
    this.height, {
    super.key,
  });

  final double height;

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      height: height,
      child: const Placeholder(),
    );
  }
}