Flutter 中 實現 單選對話框 和頁面中實現單選框

showDispatchDialog(List<Technician> techList) async {
  var alertDialogs = await showDialog(
      context: context,
      builder: (context) {
        int _techIndex = 0;
        return AlertDialog(
          title: Text("請選擇"),
 content: StatefulBuilder(builder: (context, StateSetter setState) {
            return SingleChildScrollView(
              child: ListBody(
                children: techList.asMap().keys.map((index) =>
                    Padding(
                        padding:EdgeInsets.all(5),
                        child: Row(
                          mainAxisSize: MainAxisSize.min,
                          children: <Widget>[
                            Radio(
                              value: index,
                              groupValue: _techIndex,
                              onChanged: (v) {
                                setState(() {
                                  this.technician = techList[v];
                                  _techIndex = v;
                                });
                              },
                            ),
                            Text(techList[index].name),
                          ],
                        )
                    )
                ).toList(),
              ),
            );
          }),


          actions: <Widget>[
            FlatButton(
                child: Text("取消"),
                onPressed: () {
                  Navigator.pop(context, "cancel");} ),
            FlatButton(
                child: Text("確定"),
                onPressed: (){
                  Navigator.pop(context, "confirm");
                 
                }),
          ],
        );
      });
}




頁面中實現單選框

///默認選中的單選框的值
int groupValue = 0;
///單選框的成組使用
Row buildRadioGroupRowWidget() {
  return Row(
    children: [
      Row(
        ///包裹子布局
        mainAxisSize: MainAxisSize.min,
        children: [
          Radio(
            ///此單選框綁定的值 必選參數
            value: 0,
            ///當前組中這選定的值  必選參數
            groupValue: groupValue,
            ///點擊狀態改變時的回調 必選參數
            onChanged: (v) {
              setState(() {
                this.groupValue = v;
              });
            },
          ),
          Text("語文")
        ],
      ),
      Row(
        ///包裹子布局
        mainAxisSize: MainAxisSize.min,
        children: [
          Radio(
            ///此單選框綁定的值 必選參數
            value: 1,
            ///當前組中這選定的值  必選參數
            groupValue: groupValue,
            ///點擊狀態改變時的回調 必選參數
            onChanged: (v) {
              setState(() {
                this.groupValue = v;
              });
            },
          ),
          Text("數學")
        ],
      ),
      Row(
        ///包裹子布局
        mainAxisSize: MainAxisSize.min,
        children: [
          Radio(
            ///此單選框綁定的值 必選參數
            value: 2,
            ///當前組中這選定的值  必選參數
            groupValue: groupValue,
            ///點擊狀態改變時的回調 必選參數
            onChanged: (v) {
              setState(() {
                this.groupValue = v;
              });
            },
          ),
          Text("英語")
        ],
      ),
    ],
  );
}