目前，我在Flutter中有此页面：

不幸的是，当我单击textfield时，键盘显示出来，下一个按钮出现在键盘顶部，隐藏了textfield：

我不太明白它为什么会这样。
这是我的代码：

import 'dart:ffi';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:jukebox/utils/ContainerImpl.dart';
import 'package:jukebox/utils/ElevatedButtonImpl.dart';
import 'package:jukebox/utils/TextImpl.dart';

class createAccount extends StatelessWidget {

  const createAccount({super.key});

  @override
  Widget build(BuildContext context) {

    ContainerImpl containerWidget = ContainerImpl(
        SingleChildScrollView(
          padding: const EdgeInsets.only(top: 120),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.center,
            mainAxisAlignment: MainAxisAlignment.center,
            children: const <Widget> [
              TextImpl("Créer ton profil"),
              SizedBox(height: 100),
              CircleAvatar(
                radius: 120,
                backgroundImage:NetworkImage('https://flutter.github.io/assets-for-api-docs/assets/widgets/owl.jpg') ,
              ),
              TextField(
                autofocus: false,
                scrollPadding: EdgeInsets.only(bottom: 300),
                cursorColor: Color.fromRGBO(233, 165, 208, 1),
                maxLength: 15,
                textAlign: TextAlign.center,
                style: TextStyle(
                    color: Color.fromRGBO(233, 165, 208, 0.9),
                    fontSize: 40
                ),
                decoration: InputDecoration(
                    counterText: ""
                ),
              ),
            ],
          ),
        )
    );

    AppBar appBar = AppBar(
      backgroundColor: Colors.transparent,
      elevation: 0,
      leading: IconButton(
        icon: const Icon(Icons.arrow_back, color: Colors.white),

        onPressed: () => Navigator.of(context).pop(),
      ),
    );

    return Scaffold(
      floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
      floatingActionButton: Container(
        height: 80,
        width: 350,
        margin: const EdgeInsets.all(10),
        child: ElevatedButtonImpl(onPressed: () => {}, text: "Next")
      ),
      extendBodyBehindAppBar: true,
      backgroundColor: const Color.fromRGBO(6, 24, 46, 1),
      appBar: appBar,
      body: containerWidget,
    );
  }
}

我不知道该怎么做才能防止这种情况发生，所以我在征求意见。