how to scroll search widget along with the list view result flutter

How to scroll the search widget along with the list view result flutter whenever I use singlechildscrollview it gives an error.Help me to solve the issue.
How to scroll the search widget along with the list view result flutter whenever I use singlechildscrollview it gives an error.Help me to solve the issue

import 'package:coronavirus_app/Services/states_services.dart';
import 'package:coronavirus_app/resources/sizeconfig.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:shimmer/shimmer.dart';

import '../Modal/world_countries_modal.dart';
import '../resources/colormanager.dart';
import '../resources/routesmanager.dart';

class CountriesListScreen extends ConsumerStatefulWidget {
  const CountriesListScreen({Key? key}) : super(key: key);

  @override
  ConsumerState<CountriesListScreen> createState() =>
      _CountriesListScreenState();
}

class _CountriesListScreenState extends ConsumerState<CountriesListScreen> {
  final TextEditingController searchcontroller = TextEditingController();
  @override
  Widget build(BuildContext context) {
    SizeConfig().init(context);
    StatesServices services = StatesServices();
    final countrydata = ref.watch(countrydataProvider);
    return Scaffold(
        appBar: AppBar(
          elevation: 0,
          backgroundColor: Theme.of(context).scaffoldBackgroundColor,
        ),
        body: countrydata.when(
            error: (err, stack) => Text('Error: ${err.toString()}'),
            loading: () => Shimmer.fromColors(
                  baseColor: ColorManager.grey,
                  highlightColor: ColorManager.lightGrey,
                  child: ListView.builder(
                      itemCount: 5,
                      itemBuilder: ((context, index) {
                        return Column(
                          children: [
                            ListTile(
                              title: Container(
                                height: getProportionateScreenHeight(20),
                                width: getProportionateScreenWidth(89),
                                color: ColorManager.white,
                              ),
                              leading: SizedBox(
                                  height: getProportionateScreenHeight(100),
                                  width: getProportionateScreenWidth(50),
                                  child: Container(
                                    color: ColorManager.white,
                                  )),
                              subtitle: Container(
                                height: getProportionateScreenHeight(20),
                                width: getProportionateScreenWidth(89),
                                color: ColorManager.white,
                              ),
                            )
                          ],
                        );
                      })),
                ),
            data: ((data) {
              List<WorldCountriesModal> countrieslist =
                  data.map((e) => e).toList();

              return Column(children: [
                SizedBox(
                  height: getProportionateScreenHeight(50),
                  width: double.infinity,
                  child: TextFormField(
                    controller: searchcontroller,
                    onChanged: (value) {
                      setState(() {});
                    },
                    decoration: InputDecoration(
                        contentPadding:
                            const EdgeInsets.symmetric(vertical: 10),
                        hintText: 'Search with country name',
                        prefixIcon: const Icon(Icons.search),
                        border: OutlineInputBorder(
                            borderRadius: BorderRadius.circular(50))),
                  ),
                ),
                Expanded(
                  child: ListView.builder(
                      itemCount: countrieslist.length,
                      itemBuilder: ((context, index) {
                        var data = countrieslist[index];

                        var countrydata = countrieslist[index].country;
                        if (searchcontroller.text.isEmpty) {
                          return Column(
                            children: [
                              InkWell(
                                onTap: (() {
                                  FocusScope.of(context).unfocus();
                                  Navigator.pushNamed(context, Routes.detail,
                                      arguments: data);
                                }),
                                child: ListTile(
                                  title: Text(data.country.toString()),
                                  leading: SizedBox(
                                    height: getProportionateScreenHeight(100),
                                    width: getProportionateScreenWidth(50),
                                    child: Image(
                                        image: Image.network(data
                                                .countryInfo!.flag
                                                .toString())
                                            .image),
                                  ),
                                  subtitle: Text(data.cases.toString()),
                                ),
                              )
                            ],
                          );
                        } else if (countrydata!
                            .toLowerCase()
                            .contains(searchcontroller.text.toLowerCase())) {
                          return Column(
                            children: [
                              InkWell(
                                onTap: (() {
                                  FocusScope.of(context).unfocus();
                                  Navigator.pushNamed(context, Routes.detail,
                                      arguments: data);
                                }),
                                child: ListTile(
                                  title: Text(data.country.toString()),
                                  leading: SizedBox(
                                    height: getProportionateScreenHeight(100),
                                    width: getProportionateScreenWidth(50),
                                    child: Image(
                                        image: Image.network(data
                                                .countryInfo!.flag
                                                .toString())
                                            .image),
                                  ),
                                  subtitle: Text(data.cases.toString()),
                                ),
                              )
                            ],
                          );
                        } else {
                          return Container(
                            height: 0,
                          );
                        }
                      })),
                ),
              ]);
            })

          
  }
}