|7| DraggableScrollableSheet

DraggableScrollableSheet:

import 'package:flutter/material.dart';
// import 'package:ui_flutter/core/res/utils.dart';
void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: MyHome(),
    );
  }
}
class MyHome extends StatefulWidget {
  @override  _MyHomeState createState() => _MyHomeState();
}

class _MyHomeState extends State<MyHome> {
  @override  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('DraggableScrollableSheet'),
        backgroundColor: Colors.black12,
      ),
      body: Stack(
        children: <Widget>[
          SizedBox.expand(
            child: Container(
              color: Colors.yellow[300],
            ),
          ),
          _buildDraggableScrollableSheet(),
        ],
      ),
    );
  }

  DraggableScrollableSheet _buildDraggableScrollableSheet() {
    return DraggableScrollableSheet(
      initialChildSize: 0.2,
      minChildSize: 0.2,
      maxChildSize: 0.8,
      builder: (BuildContext context, ScrollController scrollController) {
        return Container(
          decoration: BoxDecoration(
            color: Colors.blue[100],
            // border: Border.all(color: Colors.blue, width: 2),            borderRadius: BorderRadius.only(
              topLeft: Radius.circular(15),
              topRight: Radius.circular(15),
            ),
          ),
          child: Scrollbar(
            child: ListView.builder(
              controller: scrollController,
              itemCount: 25,
              itemBuilder: (BuildContext context, int index) {
                return ListTile(
                  leading: Icon(Icons.restaurant_menu),
                  title: Text('Item $index'),
                );
              },
            ),
          ),
        );
      },
    );
  }
}