如何在Flutter 中根据其父小部件高度设置图标按钮飞溅半径

我已经创建了一个CustomTextfield并将IconButton放置为后缀图标，

在这里，当我点击图标按钮时，它的开机画面半径显示大于文本字段，

在这里，我想根据它的父级来确定飞溅半径的高度.就像它是在100高的容器里一样……它必须按照它来设置……

以下是我的代码

class CustomTextField extends StatelessWidget {

  final String hint;
  final bool isitpassword;
  final TextEditingController controller;
  const CustomTextField({Key? key,required this.hint,this.isitpassword=false,required this.controller}) : super(key: key);


  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 10.0),
      child: Container(
          padding: EdgeInsets.symmetric(horizontal: 20),
          decoration: BoxDecoration(
            color: Colors.grey,
            borderRadius: BorderRadius.circular(20),
          ),

          child: TextField(
            style: TextStyle(
              fontSize: 20,color: Colors.white,),

            controller: controller,
            obscureText: isitpassword,
            decoration: InputDecoration(

              border: InputBorder.none,
              hintText: hint,
              suffixIcon: IconButton(
//what spread radius to set for better view
icon: Icon(Icons.close,color: Colors.white,),onPressed: (){
                controller.text='';
              },),

            ),
          )),
    );
  }
}