设置切换图像的抖动

Question

如何使用activeThumbImage属性为颤动中的切换按钮设置图像？我对如何为此属性设置ImageProvider值感到有些困惑？我是否可以看一下实现Switch小部件的activeThumbImage属性的示例？

Answer 1

您可以使用AssetImage或NetworkImage以获得ImageProvider适合用作的activeThumbImage。在“ 在Flutter中添加资产和图像”教程中了解有关资产图像的更多信息。

这是一些绘制以上代码的示例代码Switch：

import 'package:flutter/material.dart';

class MyHomePage extends StatefulWidget {
  MyHomePageState createState() => new MyHomePageState();
}

class MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {

  bool _enabled;

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      body: new Center(
        child: new Switch(
          value: _enabled,
          onChanged: (bool value) {
            setState(() {
              _enabled = value;
            });
          },
          activeThumbImage: new NetworkImage('https://lists.gnu.org/archive/html/emacs-devel/2015-10/pngR9b4lzUy39.png'),
          inactiveThumbImage: new NetworkImage('http://wolfrosch.com/_img/works/goodies/icon/vim@2x'),
        ),
      )
    );
  }
}

void main() {
  runApp(new MaterialApp(
    title: 'Flutter Demo',
    theme: new ThemeData(
      primarySwatch: Colors.deepPurple,
    ),
    home: new MyHomePage(),
  ));
}