How to pass Data between two Screens in Dart-CodePudding

I need to send data to another screen using dart I try to make constructor on the other screen(editdata.dart) to get the data from the main screen (readdata.dart) it is stateful widget the problem in: createState() => EditFire() EditFire class need to pass parameters but I don't have the data yet.

editdata.dart:

class EditData extends StatefulWidget {
  @override

  //Here the Error Occurs//

  State<StatefulWidget> createState() => EditFire();
}

class EditFire extends State<EditData> {
  EditFire(String ID, String date, String time, String dest, String src){
    currentID = ID;
    olddate = date;
    oldtime = time;
    _destinationcontroller.text = dest;
    _sourcecontroller.text = src;
  }
  late String currentID;
  final _destinationcontroller = TextEditingController();
  final _sourcecontroller = TextEditingController();
  late String olddate;
  late String oldtime;
}

in readdata.dart:

EditFire("2","17/6/2022","2:25","NewYork","Japan");

CodePudding user response：

First page

onPressed: () { 
      Navigator.of(context).push(MaterialPageRoute(builder: (_){
        return EditData("2","17/6/2022","2:25","NewYork","Japan");
      }));
    },

Second page in which you want to receive data

class EditData extends StatefulWidget {

 String currentID;
   String _destinationcontroller;
   String _sourcecontroller;
   String olddate;
   String oldtime;


   EditData(this.currentID, this._destinationcontroller, this._sourcecontroller,
      this.olddate, this.oldtime, {Key? key}) : super(key: key);

  @override
  State<EditData> createState() => _EditDataState();
}

class _EditDataState extends State<EditData> {

  @override
  Widget build(BuildContext context) {
    return Container(
      child: Center(child:
        Text('${widget.currentID}'),),
    );
  }
}

CodePudding user response：

To access the data of EditData to EditFire, you don't required to pass it in constructor. As you can see that EditFire is a state of EditData.

So If you want to get anything in EditFire which is used in EditData, You can used it like widget.abc

class EditData extends StatefulWidget {
  // here, in constructor of widget, we are gathering values.
  EditData(
      {required this.currentID,
      required this.olddate,
      required this.oldtime,
      Key? key})
      : super(key: key);
  String currentID;
  String olddate;
  String oldtime;

  State<StatefulWidget> createState() => EditFire();
}

// this is a state widget of EditData. so no need to pass value in constructor of state widget.

class EditFire extends State<EditData> {
  final _destinationcontroller = TextEditingController();
  final _sourcecontroller = TextEditingController();
  String? currentID;
  String? olddate;
  String? oldtime;

  @override
  void initState() {
    super.initState();

    // you can get the values like this
    currentID = widget.currentID;
    olddate = widget.olddate;
    oldtime = widget.oldtime;
  }
}

And to pass the values to EditData, you need to pass it to the constructor. like,

EditData(currentID: "", olddate: "", oldtime: "");

Hope, this will resolve your issue, still not resolved please comment with the issue.