Flutter: How can I retrieve the data of variables from QR Code I have generated with QR Code Scanner and JSON Decode?

Question

Flutter: How to retrieve the data of variables from the QR code I have generated with JSON and JSON decode?

Referring to someone's post, I'm trying to scan the QR Code I generated, in which I need to retrieve the data of a number of variables. This QR Code includes {"pickup":"Medan Gopeng Ipoh, Perak","dropoff":"Sungai Nibong, Penang", "searchdate":"Jul 1,2023","duration":"5:00 PM - 6:40 PM","totalprice":34,"passenger":2}. But when I scan the QR code I've generated, not only the scanning screen did not change as a failure, but I got an exception in the debug console.

D/DecoderThread(24361): Found barcode in 50 ms [log] FormatException: Scheme not starting with alphabetic character (at character 1) {"pickup":"Medan Gopeng Ipoh, Perak","dropoff":"Sungai Nibong, Penang","sea... ^

I want the variables to properly show their values. How can I resolve that?

These are the codes I've been working on.

Json Encode to QR Code Generator

Map<String, dynamic> myData = {
      'pickup': pickup,
      'dropoff': dropoff,
      'searchdate': searchdate,
      'duration': duration,
      'totalprice': totalprice,
      'passenger': passenger, //Number of passengers
    };
    String encodedJson = jsonEncode(myData);

child: QrImageView(
       data: encodedJson,
       size: 250,
       embeddedImageStyle: const QrEmbeddedImageStyle(
       size: Size(100,100,),
      ),
     ),

A file that's decoding QR Code Scanner while scanning the QR Code.

Future<GetProfile?> getProfileData(var url) async {
    try {
      final response = await  http.get(Uri.parse(url));
      if (response.statusCode == 200) {
        final item = json.decode(response.body);
        print(response.body);
        profile = GetProfile.fromJson(item);
      } else {
        print("An error occured");
      }
    } catch (e) {
      log(e.toString());
    }
    return profile;
  }

A Json file for QR Code Scanner for decryption

import 'dart:convert';

GetData getProfileFromJson(String str) =>
    GetData.fromJson(json.decode(str));

String getProfileToJson(GetData data) => json.encode(data.toJson());

class GetData {
  GetData({
    this.status,
    this.message,
  });

  String? status;
  Message? message;

  factory GetData.fromJson(Map<String, dynamic> json) => GetData(
        status: json["status"],
        message: Message.fromJson(json["message"]),
      );

  Map<String, dynamic> toJson() => {
        "status": status,
        "message": message?.toJson(),
      };
}

class Message {
  final String pickup;
  final String dropoff;
  final String searchdate;
  final String duration;
  final int totalprice;
  final int passenger;

  Message({
    required this.pickup,
    required this.dropoff,
    required this.searchdate,
    required this.duration,
    required this.totalprice,
    required this.passenger,
  });

  Message.fromJson(Map<String, dynamic> json):
        pickup = json["pickup"],
        dropoff = json["dropoff"],
        searchdate = json["searchdate"],
        duration = json["duration"],
        totalprice = json["totalprice"],
        passenger = json["passenger"];
        //createdAt: DateTime.parse(json["createdAt"]),
      
//final Map<String, dynamic> data = new Map<String, dynamic>();
  Map<String, dynamic> toJson() => {
    //final Map<String, dynamic> data = new Map<String, dynamic>();
      "pickup": pickup,
      "dropoff": dropoff,
      "searchdate": searchdate,
      "duration": duration,
      "totalprice": totalprice,
      "passenger": passenger,
      //return data;
      };
}