颤音的形式步骤和滚动

Question

我有形式和步进小部件的颤动视图。每个步进器都有很多小部件。当我单击步骤时，屏幕会自动滚动到新扩展的步骤的末尾。如何更改滚动以查看单击之后扩展的步骤的顶部？

（当我单击步骤2时，Step2扩展了，我从STEP2中看到了最后的小部件，而不是STEP2的第一个小部件）

代码：

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  final String title;

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

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int currentStep = 0;
  List<Step> generateSteps(int j) {
    List<Step> a = [];
    for (int i = 0; i < j; i++) {
      a.add(Step(
          title: const Text("STEP"),
          content: Column(children: generateWidgets(10))));
    }
    return a;
  }

  List<Widget> generateWidgets(int j) {
    List<Widget> a = [];

    for (int i = 0; i < j; i++) {
      a.addAll([
        Text("Field: $i"),
        TextFormField(
          decoration: const InputDecoration(
            hintText: 'Enter your email',
          ),
        ),
      ]);
    }
    return a;
  }

  @override
  Widget build(BuildContext context) {
    List<Step> ft = generateSteps(6);
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: SingleChildScrollView(
        child: Form(
            child: Stepper(
          currentStep: currentStep,
          onStepTapped: (int step) {
            setState(() {
              currentStep = step;
            });
          },
          steps: ft,
          physics: const NeverScrollableScrollPhysics(),
        )),
      ),
    );
  }
}