how to in flutter drop down value and icon but set only value?

ienter image description heremport 'package:flutter/material.dart'; import 'package:flutter_svg/svg.dart';

class ChatDropDown extends StatefulWidget { static const routeName = 'chat_dropdown';

@override _ChatDropDownState createState() => _ChatDropDownState(); }

class _ChatDropDownState extends State { List _locations = [ 'Gujarat', 'Maharatra', 'Delhi', 'Hariyana', 'Chennai', ];

String _selectedLocation; bool selectCircle = false;

@override Widget build(BuildContext context) { return Padding( padding: const EdgeInsets.only(left: 20.0, right: 20.0, top: 20.0), child: Container( alignment: Alignment.center, // height:double.infinity, decoration: BoxDecoration(boxShadow: [ BoxShadow( blurRadius: 1.5, spreadRadius: 2.0, offset: Offset(1.0, 1.0), color: Colors.grey[300].withOpacity(0.7), ) ], color: Colors.white, borderRadius: BorderRadius.circular(15.0)), child: DropdownButtonFormField( isExpanded: true, decoration: InputDecoration( // focusColor: , border: UnderlineInputBorder( borderRadius: const BorderRadius.all( const Radius.circular(10.0), ), borderSide: BorderSide.none, ), fillColor: Colors.white, errorStyle: TextStyle( color: Colors.red, fontSize: 15.0, ), filled: true, contentPadding: EdgeInsets.only(left: 15.0, right: 22.0), // hintText: "location", hintStyle: TextStyle( color: Color.fromRGBO(142, 184, 201, 1.0), fontSize: 15.0, ), // contentPadding: EdgeInsets.only(left: 10.0), // border: InputBorder.none, ), icon: Icon( Icons.keyboard_arrow_down, size: 25.0, color: Color.fromRGBO(156, 193, 208, 1.0), ), iconSize: 24, elevation: 5, style: TextStyle(color: Colors.black, fontSize: 20.0), onChanged: (String value) { if (selectCircle == false) { selectCircle = false; } else { selectCircle = true; }

        setState(() {
          _selectedLocation = value;
        });
      },
      hint: Text("Select Location"),
      value: _selectedLocation,
      items: _locations.map<DropdownMenuItem<String>>((String location) {
        return DropdownMenuItem<String>(
          value: location,
          child: Padding(
            padding: const EdgeInsets.only(top: 5.0),
            child: Column(
              children: <Widget>[
                Padding(
                  padding: const EdgeInsets.all(10.0),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: <Widget>[
                      Text(
                        location,
                      ),
                      _selectedLocation == location
                          ?  SvgPicture.asset(
                        iconCheckList,
                        height: 24.0,
                      )
                          : SvgPicture.asset(
                        iconCheckListLight,
                        height: 24.0,
                      ),
                    ],
                  ),
                ),
                SizedBox(
                  height: 10.0,
                ),
                Divider(
                  height: 1.0,
                  color: Colors.grey,
                  thickness: 1.0,
                ),
              ],
            ),
          ),
        );
      }).toList(),
    ),
  ),
);

} }