Passing data to StatefulWidget and accessing it in it's state in Flutter

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I have 2 screens in my Flutter app: list of records and screen for creating and editing records.

If I pass object to second screen that means I am going to edit this and if I pass null it means that I am creating new item. Editing screen is Stateful widget and I am not sure how to use this approach https://flutter.io/cookbook/navigation/passing-data/ for my case.

class RecordPage extends StatefulWidget {
  final Record recordObject;

  RecordPage({Key key, @required this.recordObject}) : super(key: key);

  @override
  _RecordPageState createState() => new _RecordPageState();
}

class _RecordPageState extends State<RecordPage> {
  @override
  Widget build(BuildContext context) {
   //.....
  }
}

How can I access recordObject inside _RecordPageState?

To use recordObject in _RecordPageState, you have to just write widget.objectname like below

class _RecordPageState extends State<RecordPage> {
  @override
  Widget build(BuildContext context) {
   .....
   widget.recordObject
   .....
  }
}

Simple ways to pass to and share data with widgets/pages, The simplest way to send data from a widget to another is by its constructor. Every widget along the tree can access to the data provided by our singletons/​appdata.dart';class AppDataPage extends StatefulWidget { @  Passing data to StatefulWidget and accessing it in it’s state in Flutter 0 I have 2 screens in my Flutter app: list of records and screen for creating and editing records.

class RecordPage extends StatefulWidget {
  final Record recordObject;

  RecordPage({Key key, @required this.recordObject}) : super(key: key);

  @override
  _RecordPageState createState() => new _RecordPageState(recordObject);
}

class _RecordPageState extends State<RecordPage> {
  Record  recordObject
 _RecordPageState(this. recordObject);  //constructor
  @override
  Widget build(BuildContext context) {.    //closure has access
   //.....
  }
}

How to pass data from Stateful Widget Constructor to its state class , In this article, we will see how to pass data from outside of Stateful Widget to its internal State class through its constructor. Therefore, Stateful. Passing data to StatefulWidget and accessing it in it's state in Flutter (3 answers) Closed 9 months ago . I have a string that contains an information that was passed from previous classes.

Full Example

You don't need to pass parameters to State using it's constructor. You can easily access these using widget.myField.

class MyRecord extends StatefulWidget {
  final String recordName;
  const MyRecord(this.recordName);

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

class MyRecordState extends State<MyRecord> {
  @override
  Widget build(BuildContext context) {
    return Text(widget.recordName); // Here you direct access using widget
  }
}

Flutter, home: new MyHomePage(),. ); } } class MyHomePage extends StatefulWidget {. @override. _MyHomePageState createState() => new _MyHomePageState();. }. 2) On the second screen, passing the data to the Navigator.pop back to the first screen. Example: While in the previous section we passed a data instance to the second screen, in this one, we are going to push the second screen and wait for the second screen to pop, receiving from it the data.

Send data to a new screen, A stateless widget never changes. Passing data to StatefulWidget and accessing it in it's state in Flutter. objectname like below class _RecordPageState extends  Now, I have to access the instance of an object created in first widget in the second widget, but I am not so sure how I can do this in flutter when creating widgets. One possible solution I thought of is to declare the two widgets in just one dart file instead of two dart files for two layouts, but I am curious if we can do it by declaring in

Passing Data to Stateful Widget, I'm wondering what the recommended way of passing data to a stateful widget, while creating it, is. You can easily access these in State class using widget. MyApp is StatelessWidget which will host our StateFulWidget as the first page, that's why we are passing MainPage (to be created) as object: Now right click on lib folder and click on new and add package to folder by name widgets. Add new dart file by name mainpage.dart, which will have code of our Stateful widget.

Flutter - Passing data to the next page, Learn how to pass and update account data between screens and widgets like wherever we initialize our MaterialApp , then access and change it directly MyHomePage(), ); } } class MyHomePage extends StatefulWidget  A StatefulWidget keeps the same State object when moving from one location in the tree to another if its creator used a GlobalKey for its key. Because a widget with a GlobalKey can be used in at most one location in the tree, a widget that uses a GlobalKey has at most one associated element.

Comments
  • Possible duplicate of Passing Data to a Stateful Widget
  • Those who are new to Flutter, do not forget to define widget like '@override RecordPage get widget => super.widget;'
  • @hhk Why is that necessary?
  • Should't the recordObject be part of the State class? Logically, having it in StatefulWidget is incorrect (in terms of cohesion). Besides, all fields of StatefulWidget should be immutable - what if you want to change the recordObject reference?
  • I have exactly the same and it's not working doing something like Text(widget.recordObject), it says that my var is null
  • Please explain why this is a statefull widget.
  • @atilkan because OP initial script is a StatefulWidget, he just added some lines to fit the needs.
  • I do not think that having recordObject field both in State and StatefulWidget classes is such a good idea (even though I saw tutorials doing exactly this). The approach of accessing fields of StatefulWidget by using widget field of State class seem like a more correct approach (even though it has its own problems)