我想在选择一个单选按钮的时候引起用户对提交按钮的注意,我想知道是否还有什么可以实现这一点。我看过RaisedButton文档,但似乎没有任何闪烁或摇动按钮的属性。例如,下面的代码最初没有选择单选按钮,因此按钮显示为灰色,一旦在多个单选按钮之间做出选择,提交的RaisedButton onPressed属性值不再为null,而是替换为所需的操作;但是我还想要一种情况,如果选择了不同的单选按钮,有一些方法可以向提交按钮添加一些动作(闪烁/摇动按钮),但不能更改onPressed属性
new Radio<int>(
value: 1,
groupValue: 0,
onChanged: handleRadioValue
)
new RaisedButton(
child: const Text('SUBMIT')
onPressed: selected
)
handleRadioValue(){
selected = groupValue == 0 ? null : submitButton();
//change Raised button to attract attention}
答案 0 :(得分:1)
您可以通过设置color
RaisedButton
的动画来吸引注意力。此示例通过将其颜色更改为当前主题RaisedButton
并返回时,将单选按钮选择更改时引起注意disabledColor
。
import 'dart:math';
import 'package:flutter/material.dart';
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
home: new MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key}) : super(key: key);
@override
createState() => new MyHomePageState();
}
class MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
AnimationController _controller;
int _radioValue;
@override initState() {
_controller = new AnimationController(
vsync: this,
duration: const Duration(milliseconds: 100),
)..addStatusListener((AnimationStatus status) {
if (status == AnimationStatus.completed)
_controller.reverse();
});
super.initState();
}
void _handleRadioValue(int value) {
// Don't animate the first time that the radio value is set
if (_radioValue != null)
_controller.forward();
setState(() {
_radioValue = value;
});
}
@override
Widget build(BuildContext context) {
ThemeData theme = Theme.of(context);
return new Scaffold(
body: new Center(
child: new Column(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.center,
children: [
new Radio<int>(
value: 0,
groupValue: _radioValue,
onChanged: _handleRadioValue
),
new Radio<int>(
value: 1,
groupValue: _radioValue,
onChanged: _handleRadioValue
),
new AnimatedBuilder(
child: const Text('SUBMIT'),
animation: _controller,
builder: (BuildContext context, Widget child) {
return new RaisedButton(
color: new ColorTween(
begin: theme.primaryColor,
end: theme.disabledColor,
).animate(_controller).value,
colorBrightness: Brightness.dark,
child: child,
onPressed: _radioValue == null ?
null :
() => print('submit')
);
}
)
],
),
),
);
}
@override
void dispose() {
_controller.dispose();
super.dispose();
}
}