Flutter怎么实现单选按钮

效果图如下&＃xff1a;

import &＃39;package:flutter/material.dart&＃39;;class AddPage extends StatefulWidget {&＃64;overrideState createState() {// TODO: implement createStatereturn AddPageState();}
}
class AddPageState extends State{num groupValue &＃61; 1;
Widget _topsection(){return Container(child:Row(children: [],),);
}&＃64;overrideWidget build(BuildContext context) {return Scaffold(appBar: AppBar(elevation: 0,title: Text(&＃39;添加信息&＃39;,style: TextStyle(fontWeight: FontWeight.bold),),centerTitle: true,leading:Icon(Icons.arrow_back_ios),actions: [Container(padding: EdgeInsets.only(top: 13.0,right: 10.0),child: Text(&＃39;完成&＃39;,textAlign: TextAlign.center,style: TextStyle(fontSize: 18.0,),),)],),body: Column(children: [_topsection(),Container(child: Column(children: [Row(children: [Radio(groupValue: groupValue,value: 1,onChanged: (value){groupValue&＃61;value;setState((){});},),Text(&＃39;工作计划&＃39;)],),Row(children: [Radio(value: 2,groupValue: groupValue,onChanged: (value){groupValue&＃61;value;setState((){});},),Text(&＃39;工作计划2&＃39;)],),Row(children: [Radio(value: 3,groupValue: groupValue,onChanged: (value){groupValue&＃61;value;setState((){});},),Text(&＃39;工作计划3&＃39;)],),],))],),);}
}