[英]Change Background Color of Elevated Button OnPressed in Flutter
我需要更改提升按鈕的背景顏色,單擊以將其指示為已選中。 我試過這個。
class _MyState extends State<MyPage> {
bool _flag = true;
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: ElevatedButton(
onPressed: () => setState(() => _flag = !_flag),
child: Text(_flag ? 'Red' : 'Green'),
style: ElevatedButton.styleFrom(
backgroundColor: _flag ? Colors.red : Colors.teal,
),
),
),
);
}
}
在 onPressed() 上:顏色沒有改變
在 DartPad 上,您的代碼可以正常工作Link to dartpad 。
確保您正確實施了有狀態小部件:
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(),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({
Key? key,
}) : super(key: key);
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
bool _flag = true;
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: ElevatedButton(
onPressed: () => setState(() => _flag = !_flag),
child: Text(_flag ? 'Red' : 'Green'),
style: ElevatedButton.styleFrom(
backgroundColor: _flag ? Colors.red : Colors.teal,
),
),
),
);
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.