flutter - flutter 的可拖动滚动表

有谁知道为什么我的可拖动滚动页不起作用或者为什么我看不到它？
我以另一种可行的方式尝试了它，但是我没有使用SafeArea-Widget，

import 'package:flutter/material.dart';
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: PreferredSize(
        preferredSize: Size.fromHeight(100.0),
        child: AppBar(
          //AppBar
      ),
      body: SafeArea(
        child: ListView(
          children: <Widget>[
            Padding(
              padding: EdgeInsets.only(left: 20),
              child: Text(
                dateday,
                style: TextStyle(
                  color: Color(0xff2C8E5D),
                  fontSize: 150,
                ),
              ),
            ),
            SizedBox.expand(
              child: DraggableScrollableSheet(builder:
                  (BuildContext context, ScrollController scrollController) {
                return Container(
                  color: Colors.red,
                  child: ListView.builder(
                      controller: scrollController,
                      itemCount: 25,
                      itemBuilder: (BuildContext context, int index) {
                        return ListTile(title: Text("Item $index"));
                      }),
                );
              }),
            ),
          ],
        ),
      ),
    );
  }
}

谢谢你的帮助!

最佳答案

用ListView替换Stack:

body: SafeArea(
        child: Stack(
          children: <Widget>[
            Padding(
              padding: EdgeInsets.only(left: 20),
              child: Text(
                dateday,
                style: TextStyle(
                  color: Color(0xff2C8E5D),
                  fontSize: 150,
                ),
              ),
            ),
            SizedBox.expand(
              child: DraggableScrollableSheet(
                  builder:
                  (BuildContext context, ScrollController scrollController) {
                return Container(
                  color: Colors.red,
                  child: ListView.builder(
                      controller: scrollController,
                      itemCount: 25,
                      itemBuilder: (BuildContext context, int index) {
                        return ListTile(title: Text("Item $index"));
                      }),
                );
              }),
            ),
          ],
        ),
      ),