Flutter web:如何以步进形式进行水平滚动?

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【中文标题】Flutter web:如何以步进形式进行水平滚动?【英文标题】:Flutter web: How to make horizontal scroll in stepper form? 【发布时间】:2021-08-05 12:34:03 【问题描述】:

我正在尝试使用步进器制作一个颤动的网络表单,并且我正在为小尺寸屏幕做实验。我已经使用物理:ClampingScrollPhysics() 方法完成了垂直滚动。但是,我无法在步进步骤中进行水平滚动。我想让单选按钮水平滚动,以便隐藏错误消息并且文本离开屏幕,用户可以滚动到该部分。我已经使用 SingleChildCcrollView(crollDirection: Axis.horizo​​ntal) 但它没有用。图片是

flutter程序的代码如下:-

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget 
  @override
  Widget build(BuildContext context) 
    return new MaterialApp(
      title: 'Flutter Stepper Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Stepper Tutorial'),
    );
  


class MyHomePage extends StatefulWidget 
  MyHomePage(Key key, this.title) : super(key: key);
  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();


class _MyHomePageState extends State<MyHomePage> 
  int _currentStep = 0;
  TextEditingController nameController = TextEditingController();
  TextEditingController emailController = TextEditingController();
  TextEditingController addressController = TextEditingController();
  List<String> demoList = [];

  @override
  Widget build(BuildContext context) 
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: Column(
        children: <Widget>[
          Row(
            mainAxisAlignment: MainAxisAlignment.start,
          ),
          Expanded(
            child: SingleChildScrollView(
              // scrollDirection: Axis.horizontal,
              child: Stepper(
                physics: ClampingScrollPhysics(),
                steps: _mySteps(),
                currentStep: this._currentStep,
                onStepTapped: (step) 
                  setState(
                    () 
                      this._currentStep = step;
                    ,
                  );
                ,
                onStepContinue: () 
                  setState(
                    () 
                      if (this._currentStep < this._mySteps().length - 1) 
                        this._currentStep = this._currentStep + 1;
                      
                    ,
                  );
                ,
                onStepCancel: () 
                  setState(
                    () 
                      if (this._currentStep > 0) 
                        this._currentStep = this._currentStep - 1;
                       else 
                        this._currentStep = 0;
                      
                    ,
                  );
                ,
              ),
            ),
          ),
          demoList.isEmpty
              ? Text("")
              : Column(
                  children: demoList.map((e) 
                    return Text(e);
                  ).toList(),
                ),
          ElevatedButton(
            onPressed: () 
              demoList = [];
              viewList();
            ,
            child: Text("Click to see List"),
          ),
        ],
      ),
    );
  

  viewList() 
    if (nameController.text.isEmpty ||
        emailController.text.isEmpty ||
        addressController.text.isEmpty) 
      setState(
        () 
          if (nameController.text.isEmpty) 
            demoList.add("Name field is empty");
           else if (emailController.text.isEmpty) 
            demoList.add("Email field is Empty");
           else if (addressController.text.isEmpty) 
            demoList.add("Address field is empty");
          
        ,
      );
     else 
      demoList.add(nameController.text);
      demoList.add(emailController.text);
      demoList.add(addressController.text);

      setState(
        () 
          demoList = demoList;
        ,
      );
    
  

  List<Step> _mySteps() 
    List<Step> _steps = [
      Step(
        title: Text('Name'),
        content: TextField(
          controller: nameController,
        ),
        isActive: _currentStep >= 0,
      ),
      Step(
        title: Text('Email'),
        content: TextField(
          controller: emailController,
        ),
        isActive: _currentStep >= 1,
      ),
      Step(
        title: Text('Address'),
        content: TextField(
          controller: addressController,
        ),
        isActive: _currentStep >= 2,
      ),
      Step(
        title: Text('Number'),
        content: Row(
          children: <Widget>[
            SingleChildScrollView(
              physics: ClampingScrollPhysics(),
            ),
            SafeArea(
              child: SingleChildScrollView(
                scrollDirection: Axis.horizontal,
                child: Form(
                  child: Row(
                    children: <Widget>[
                      Radio(
                        value: "1",
                      ),
                      Text("1"),
                      Radio(
                        value: "2",
                      ),
                      Text("2"),
                      Radio(
                        value: "3",
                      ),
                      Text("3"),
                      Radio(
                        value: "4",
                      ),
                      Text("4"),
                      Radio(
                        value: "5",
                      ),
                      Text("5"),
                      Radio(
                        value: "6",
                      ),
                      Text("6"),
                      Radio(
                        value: "7",
                      ),
                      Text("7"),
                      Radio(
                        value: "8",
                      ),
                      Text("8"),
                      Radio(
                        value: "9",
                      ),
                      Text("9"),
                    ],
                  ),
                ),
              ),
            )
          ],
        ),
        isActive: _currentStep >= 2,
      ),
    ];
    return _steps;
  

【问题讨论】:

【参考方案1】:

您可以只使用ListView 并将scrollDirection 设置为水平。 Container 之所以存在是因为它需要一些东西来给它一个大小。

Step(
        title: Text('Number'),
        content: Container(
          height: 100,
          child: ListView(
            scrollDirection: Axis.horizontal,
            children: [
              Radio(
                value: "1",
              ),
              Center(child: Text("1")),
              Radio(
                value: "2",
              ),
              Center(child: Text("1")),
              Radio(
                value: "3",
              ),
              Center(child: Text("3")),
              Radio(
                value: "4",
              ),
              Center(child: Text("4")),
              Radio(
                value: "5",
              ),
              Center(child: Text("5")),
              Radio(
                value: "6",
              ),
              Center(child: Text("6")),
              Radio(
                value: "7",
              ),
              Center(child: Text("7")),
              Radio(
                value: "8",
              ),
              Center(child: Text("8")),
              Radio(
                value: "9",
              ),
              Center(child: Text("9")),
            ],
          ),
        ),
        isActive: _currentStep >= 2,
      ),

【讨论】:

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