另一个很酷的解决方案在2021年也适用:

TextButton(
    child: Padding(
        padding: const EdgeInsets.all(5.0),
        child: Text('Follow Us'.toUpperCase()),
    ),
    style: TextButton.styleFrom(
        backgroundColor: Colors.amber,
        shadowColor: Colors.red,
        elevation: 2,
        textStyle: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
        shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(5.0),)
    ),
    onPressed: () {
        print('Pressed');
    },
),

在容器小部件中包装一个TextButton，如下所示:

Container(
  decoration: BoxDecoration(
    borderRadius: BorderRadius.circular(5),
    border: Border.all(color: Colors.black),
  ),
  child: TextButton(
    onPressed: () {
      // To do
    },
    child: Text("Go to Change Language Screen "),
  ),
)

现在我们有一个图标按钮来实现圆形按钮点击和覆盖。但是，背景颜色还不可用，但同样可以通过Circle头像小部件实现，如下所示:

CircleAvatar(
    backgroundColor: const Color(0xffF4F3FA),
    child: IconButton(
        onPressed: () => FlushbarHelper.createInformation(
                             message: 'Work in progress...')
                             .show(context),
        icon: Icon(Icons.more_vert),
    ),
),

创建圆角按钮的不同方法如下:

用ElevatedButton. stylefrom

ElevatedButton(
          style: ElevatedButton.styleFrom(
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(30.0),
            ),
          ),
          onPressed: () {},
          child:
              Text("Buy now".toUpperCase(), style: TextStyle(fontSize: 14)),
        ),

用ButtonStyle提升按钮

ElevatedButton(
          style: ButtonStyle(
              shape: MaterialStateProperty.all<RoundedRectangleBorder>(
                  RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(50.0),
          ))),
          onPressed: () {},
          child: Text("Submit".toUpperCase()),
        ),

圆形按钮的实际演示可以在下面的Dartpad链接中找到:

圆形按钮演示例子在达特pad

使用Flutter版本2，请尝试以下操作

ElevatedButton(
    style: ButtonStyle(
        shape: MaterialStateProperty.all<OutlinedBorder>(
            RoundedRectangleBorder(
                side:
                    BorderSide(width: 1.0, color: Colors.red,
                borderRadius:
                    BorderRadius.circular(5.0),),),
        backgroundColor: MaterialStateProperty.all<Color>(Colors.red),
        foregroundColor: MaterialStateProperty.all<Color>(Colors.green),
        elevation:
            MaterialStateProperty.all<double>(8.0),
        padding: MaterialStateProperty.all<EdgeInsetsGeometry>(
            const EdgeInsets.symmetric(
                horizontal: 15.0,
                vertical: 10.0),),),
    onPressed: (){},
    child: Text('Button'),)

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),
                    ),
                  ),
                ),
              ),