如何在Flutter中更改CupertinoSwitch的大小？

Question

我想在Flutter中更改CupertinoSwitch的大小。我曾尝试将开关放入“容器”中，但是更改容器的大小不会影响该开关。

Answer 1

您可以在下面复制粘贴运行完整代码
您可以使用Transform.scale并设置scale，1表示普通尺寸，0.8表示较小的尺寸

代码段

Transform.scale(
                        scale: 0.8,
                        child: CupertinoSwitch(
                          value: _switchValue,
                          onChanged: (bool value) {
                            setState(() {
                              _switchValue = value;
                            });
                          },
                        ),
                      )

工作演示

完整代码

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';

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

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

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {    
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {    
    return Scaffold(
      appBar: AppBar(        
        title: Text(widget.title),
      ),
      body: Center(        
        child: Column(          
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), 
    );
  }
}

class CupertinoSwitchDemo extends StatefulWidget {
  static const String routeName = '/cupertino/switch';

  @override
  _CupertinoSwitchDemoState createState() => _CupertinoSwitchDemoState();
}

class _CupertinoSwitchDemoState extends State<CupertinoSwitchDemo> {

  bool _switchValue = false;

  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      navigationBar: CupertinoNavigationBar(
        middle: const Text('Switch'),
        // We're specifying a back label here because the previous page is a
        // Material page. CupertinoPageRoutes could auto-populate these back
        // labels.
        previousPageTitle: 'Cupertino',
        //trailing: CupertinoDemoDocumentationButton(CupertinoSwitchDemo.routeName),
      ),
      child: DefaultTextStyle(
        style: CupertinoTheme.of(context).textTheme.textStyle,
        child: SafeArea(
          child: Center(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.spaceAround,
              children: <Widget>[
                Semantics(
                  container: true,
                  child: Column(
                    children: <Widget>[
                      Transform.scale(
                        scale: 0.8,
                        child: CupertinoSwitch(
                          value: _switchValue,
                          onChanged: (bool value) {
                            setState(() {
                              _switchValue = value;
                            });
                          },
                        ),
                      ),
                      Text(
                          "Enabled - ${_switchValue ? "On" : "Off"}"
                      ),
                    ],
                  ),
                ),
                Semantics(
                  container: true,
                  child: Column(
                    children: const <Widget>[
                      CupertinoSwitch(
                        value: true,
                        onChanged: null,
                      ),
                      Text(
                          'Disabled - On'
                      ),
                    ],
                  ),
                ),
                Semantics(
                  container: true,
                  child: Column(
                    children: const <Widget>[
                      CupertinoSwitch(
                        value: false,
                        onChanged: null,
                      ),
                      Text(
                          'Disabled - Off'
                      ),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}