Basic Flutter implementation of the Google Photos draggable menu

main.dart

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      debugShowCheckedModeBanner: false,
      home: const ShowMenuWrapper(child: MyHomePage(title: 'Google Fothos')),
    );
  }
}

class MyHomePage extends StatelessWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);

  final String title;

  @override
  Widget build(BuildContext context) {
    return Stack(
      children: [
        Scaffold(
          appBar: AppBar(
            title: Text(title),
            actions: [
              InkWell(
                onTap: () {
                  ShowMenuWrapper.of(context).toggleMenu();
                },
                child: const _Avatar(),
              ),
            ],
          ),
          body: const _Grid(),
        ),
        if (ShowMenuWrapper.of(context).showMenu) const MenuPage(),
      ],
    );
  }
}

class MenuPage extends StatelessWidget {
  const MenuPage({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return DraggableScrollableSheet(
      initialChildSize: 0.9,
      builder: (context, scrollController) {
        final canTakeInsets = scrollController.hasClients;
        var insets = 16.0;
        if (canTakeInsets) {
          final height = MediaQuery.of(context).size.height;
          insets =
              ((height - scrollController.position.viewportDimension) / 5 - 1)
                  .clamp(0.0, 16.0);
        }
        return Listener(
          onPointerUp: (_) {
            if (insets >= 16.0 && ShowMenuWrapper.of(context).showMenu) {
              // ShowMenuWrapper.of(context).toggleMenu();
            }
          },
          child: _ListContent(
            insets: insets,
            scrollController: scrollController,
          ),
        );
      },
    );
  }
}

class _ListContent extends StatelessWidget {
  const _ListContent({
    Key? key,
    required this.insets,
    required this.scrollController,
  }) : super(key: key);

  final double insets;
  final ScrollController scrollController;

  @override
  Widget build(BuildContext context) {
    final top = (32 - 2 * insets);
    return Padding(
      padding: EdgeInsets.symmetric(
        horizontal: insets,
      ),
      child: Material(
        borderRadius: BorderRadius.circular(16),
        child: Stack(
          children: [
            ListView(
              controller: scrollController,
              physics: const ClampingScrollPhysics(),
              padding: EdgeInsets.zero,
              children: [
                Padding(
                  padding: EdgeInsets.only(top: 16 + top, bottom: 8),
                  child: const FlutterLogo(
                    style: FlutterLogoStyle.horizontal,
                  ),
                ),
                const ListTile(
                  leading: _Avatar(),
                  title: Text('John Doe'),
                  subtitle: Text('example@example.com'),
                ),
                ListTile(
                  title: OutlinedButton(
                    onPressed: () {},
                    child: const Text('Manage your account'),
                  ),
                ),
                const Divider(),
                const ListTile(
                  leading: Padding(
                    padding: EdgeInsets.all(8.0),
                    child: Icon(Icons.cloud_outlined),
                  ),
                  title: Text('Account storage'),
                  subtitle: LinearProgressIndicator(
                    value: 0.5,
                  ),
                ),
                const Divider(),
                const ListTile(
                  leading: Padding(
                    padding: EdgeInsets.all(8.0),
                    child: SizedBox(
                      height: 16,
                      width: 16,
                      child: CircularProgressIndicator(
                        strokeWidth: 2,
                      ),
                    ),
                  ),
                  title: Text('Save up to 100GB of data'),
                  subtitle: Text('Lorem ipsum dolor sit amet'),
                ),
                const Divider(),
                const ListTile(
                  leading: Padding(
                    padding: EdgeInsets.all(8.0),
                    child: Icon(Icons.settings_outlined),
                  ),
                  title: Text('Settings'),
                ),
              ],
            ),
            Padding(
              padding: EdgeInsets.only(top: top),
              child: IconButton(
                onPressed: () {
                  ShowMenuWrapper.of(context).toggleMenu();
                },
                icon: const Icon(Icons.close),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class ShowMenuWrapper extends StatefulWidget {
  const ShowMenuWrapper({Key? key, required this.child}) : super(key: key);

  final Widget child;

  static _ShowMenuWrapperState of(BuildContext context) {
    final _ShowMenuWrapperState? result =
        context.dependOnInheritedWidgetOfExactType<ShowMenuController>()?.state;
    assert(result != null, 'No ShowMenuController found in context');
    return result!;
  }

  @override
  _ShowMenuWrapperState createState() => _ShowMenuWrapperState();
}

class _ShowMenuWrapperState extends State<ShowMenuWrapper> {
  bool showMenu = false;

  void toggleMenu() {
    setState(() {
      showMenu = !showMenu;
    });
  }

  @override
  Widget build(BuildContext context) {
    return ShowMenuController(
      showMenu: showMenu,
      child: widget.child,
      state: this,
    );
  }
}

class ShowMenuController extends InheritedWidget {
  const ShowMenuController({
    Key? key,
    required this.showMenu,
    required Widget child,
    required this.state,
  }) : super(key: key, child: child);

  final bool showMenu;
  final _ShowMenuWrapperState state;

  @override
  bool updateShouldNotify(ShowMenuController oldWidget) =>
      showMenu != oldWidget.showMenu;
}

class _Grid extends StatelessWidget {
  const _Grid({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return GridView.count(
      crossAxisCount: 3,
      children: [
        for (int i in List.generate(100, (index) => index))
          ColoredBox(
              // some random color
              color: Color(
                  (0xFF000000 + i * (0xFFFFFFFF - 0xFF000000) / 100).toInt())),
      ],
    );
  }
}

class _Avatar extends StatelessWidget {
  const _Avatar({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const CircleAvatar(
      backgroundImage: NetworkImage('https://thispersondoesnotexist.com/image'),
    );
  }
}