import 'package:flutter/material.dart';class LearnRadioButton extends StatefulWidget{  @override  State
     
       createState() {    return new _LearnRadioButton();  }}class _LearnRadioButton extends State
      
       {  int groupValue=1;  @override  Widget build(BuildContext context) {    return new Scaffold(      body: new Column(        mainAxisAlignment: MainAxisAlignment.center,        children: 
       
        [          new Radio(value: 0, groupValue: 0, onChanged: null),//onChanged为null表示按钮不可用          new Radio(              value: 1,              groupValue: groupValue,//当value和groupValue一致的时候则选中              activeColor: Colors.red,              onChanged: (T){                updateGroupValue(T);              }          ),          new Radio(              value: 2,              groupValue: groupValue,              onChanged: (T){                updateGroupValue(T);              }          ),          new Radio(              value: 3,              groupValue: groupValue,              onChanged: (T){                updateGroupValue(T);              }          ),          new Radio(              value: 4,              groupValue: groupValue,              onChanged: (T){                updateGroupValue(T);              }          ),          new Radio(              value: 5,              groupValue: groupValue,              onChanged: (T){                updateGroupValue(T);              }          ),          new Radio(              value: 6,              groupValue: groupValue,              onChanged: (T){                updateGroupValue(T);              }          ),          new RadioListTile(              value: 7,              groupValue: groupValue,              title: new Text('小张'),              onChanged: (T){                updateGroupValue(T);              }),          new RadioListTile(              value: 8,              groupValue: groupValue,              title: new Text('小林'),              onChanged: (T){                updateGroupValue(T);              }),          new RadioListTile(              value: 9,              groupValue: groupValue,              title: new Text('小王'),              onChanged: (T){                updateGroupValue(T);              }),          new RadioListTile(              value: 10,              groupValue: groupValue,              title: new Text('小红'),              onChanged: (T){                updateGroupValue(T);              })        ],      ),    );  }  void updateGroupValue(int v){    setState(() {      groupValue=v;    });  }}