我目前正在Flutter开发一个Android应用程序。我如何添加一个圆形按钮?
当前回答
还有另一种方法来做到这一点-只是使用FloatingActionButton适当的圆形按钮。
Scaffold(
appBar: AppBar(
title: const Text('Floating Action Button'),
),
body: const Center(child: Text('Press the button below!')),
floatingActionButton: FloatingActionButton(
onPressed: () {
// Add your onPressed code here!
},
backgroundColor: Colors.green,
child: const Icon(Icons.navigation),
),
)
其他回答
1. 解决方案概述
FlatButton和RaisedButton已弃用。
因此,你可以使用形状放在样式属性,为TextButton和ElevatedButton。
自Flutter 2.0以来有一些变化:
style:属性类型已更改为ButtonStyle shape:属性类型已更改为MaterialStateProperty<T>
2. 圆形的按钮
在style属性中存在shape属性:
style: ButtonStyle(
shape: MaterialStateProperty.all<RoundedRectangleBorder>(
RoundedRectangleBorder(
borderRadius: BorderRadius.circular(18.0),
side: BorderSide(color: Colors.red)
)
)
)
方形按钮
对于方形按钮,您可以使用ElevatedButton或添加其他方式:
style: ButtonStyle(
shape: MaterialStateProperty.all<RoundedRectangleBorder>(
RoundedRectangleBorder(
borderRadius: BorderRadius.zero,
side: BorderSide(color: Colors.red)
)
)
)
完整的示例
Row(
mainAxisAlignment: MainAxisAlignment.end,
children: [
TextButton(
child: Text(
"Add to cart".toUpperCase(),
style: TextStyle(fontSize: 14)
),
style: ButtonStyle(
padding: MaterialStateProperty.all<EdgeInsets>(EdgeInsets.all(15)),
foregroundColor: MaterialStateProperty.all<Color>(Colors.red),
shape: MaterialStateProperty.all<RoundedRectangleBorder>(
RoundedRectangleBorder(
borderRadius: BorderRadius.circular(18.0),
side: BorderSide(color: Colors.red)
)
)
),
onPressed: () => null
),
SizedBox(width: 10),
ElevatedButton(
child: Text(
"Buy now".toUpperCase(),
style: TextStyle(fontSize: 14)
),
style: ButtonStyle(
foregroundColor: MaterialStateProperty.all<Color>(Colors.white),
backgroundColor: MaterialStateProperty.all<Color>(Colors.red),
shape: MaterialStateProperty.all<RoundedRectangleBorder>(
RoundedRectangleBorder(
borderRadius: BorderRadius.zero,
side: BorderSide(color: Colors.red)
)
)
),
onPressed: () => null
)
]
)
您可以简单地使用RaisedButton
Padding(
padding: EdgeInsets.only(left: 150.0, right: 0.0),
child: RaisedButton(
textColor: Colors.white,
color: Colors.black,
child: Text("Search"),
onPressed: () {},
shape: new RoundedRectangleBorder(
borderRadius: new BorderRadius.circular(30.0),
),
),
)
输出:
更多信息:RSCoder
您可以使用下面的代码创建一个渐变颜色的圆形按钮。
Container(
width: 130.0,
height: 43.0,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(30.0),
gradient: LinearGradient(
// Where the linear gradient begins and ends
begin: Alignment.topRight,
end: Alignment.bottomLeft,
// Add one stop for each color. Stops should increase from 0 to 1
stops: [0.1, 0.9],
colors: [
// Colors are easy thanks to Flutter's Colors class.
Color(0xff1d83ab),
Color(0xff0cbab8),
],
),
),
child: FlatButton(
child: Text(
'Sign In',
style: TextStyle(
fontSize: 16.0,
fontFamily: 'Righteous',
fontWeight: FontWeight.w600,
),
),
textColor: Colors.white,
color: Colors.transparent,
shape:
RoundedRectangleBorder(borderRadius: BorderRadius.circular(30.0)),
onPressed: () {
},
),
);
在新的更新颤振3.0颤振使用材料3指南。
根据它,按钮的默认边框被四舍五入。
默认按钮
ElevatedButton(
onPressed: () {}, child: const Text("Default Button ")),
边界半径为零的按钮
ElevatedButton(
style: ElevatedButton.styleFrom(
shape: const RoundedRectangleBorder(
borderRadius: BorderRadius.zero)),
onPressed: () {},
child: const Text("Border Radius Zero ")),
带有自定义边界半径的按钮
ElevatedButton(
style: ElevatedButton.styleFrom(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(50))),
onPressed: () {},
child: const Text("Border Radius Custom ")),
注意:你可以对FilledButton, TextButton等使用相同的逻辑。
按钮样式请参考https://m3.material.io/components/all-buttons。
在Null安全之后,使用ElevatedButton而不是RaisedButton,因为RaisedButton就像文档中说的那样被贬低了。
child: ElevatedButton(
onPressed: () {},
child: const Text('Add item to the list'),
style: ButtonStyle(
backgroundColor:
MaterialStateProperty.all<Color>(Common.buttonColor),
shape: MaterialStateProperty.all<RoundedRectangleBorder>(
RoundedRectangleBorder(
borderRadius: BorderRadius.circular(18.0),
),
),
),
),