How to pass data from alertdialog to page in flutter?

Question

I am passing data from my alertdialog to item of listview.

Where I can find information about it?

I tried use TextEditingController, with Navigation Routes. And I used materials from this Tutorial

This is my code:

    class MeasurementsScreen extends StatefulWidget {
  @override
  _MeasurementsScreenState createState() => _MeasurementsScreenState();
}


class _MeasurementsScreenState extends State<MeasurementsScreen> {
  List<_ListItem> listItems;
  String lastSelectedValue;
  var name = ["Рост", "Вес"];
  var indication = ["Введите ваш рост", "Введите ваш вес"];
  TextEditingController customcintroller;

  void navigationPageProgrammTrainingHandler() {
    Navigator.of(context).push(MaterialPageRoute(
        builder: (BuildContext context) => ProgrammTrainingHandler()),
    );
  }
  @override
  void initState() {
    super.initState();
    initListItems();
  }

  Future<String> createAlertDialog(BuildContext context, int indexAl){
    customcintroller = TextEditingController();
    if(indexAl < 2){
      return showDialog(context: context, builder: (context){
        return AlertDialog(
          title: Text(name[indexAl]),
          content: TextField(
            textDirection: TextDirection.ltr,
            controller: customcintroller,
            style: TextStyle(
                color: Colors.lightGreen[400],
                fontSize: 18.5),
            decoration: InputDecoration(
              contentPadding: EdgeInsets.only(bottom: 4.0),
              labelText: indication[indexAl],
              alignLabelWithHint: false,
            ),
            keyboardType: TextInputType.phone,
            textInputAction: TextInputAction.done,
          ),
          actions: <Widget>[
            FlatButton(
              child: const Text('ОТМЕНА'),
              onPressed: () {
                Navigator.of(context).pop();
              },
            ),
            FlatButton(
              child: const Text('ОК'),
              onPressed: () {
                Navigator.of(context).pop(customcintroller.text.toString());
              },
            ),
          ],
        );
      });
    } else if (indexAl > 1){
      navigationPageProgrammTrainingHandler();
    }

  }


  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      backgroundColor: Color(0xff2b2b2b),
      appBar: AppBar(
        title: Text(
          'Замеры',
          style: new TextStyle(
            color: Colors.white,

          ),),
        leading: IconButton(
          icon:Icon(Icons.arrow_back),
          color: Colors.white ,
          onPressed:() => Navigator.of(context).pop(),
        ),
      ),
      body: ListView.builder(
        physics: BouncingScrollPhysics(),
        itemCount: listItems.length,
        itemBuilder: (BuildContext ctxt, int index){
          return GestureDetector(
              child: listItems[index],
              onTap: () {
                  createAlertDialog(context, index).then((onValue){

                  });
              }
          );
        },
      ),
    );
  }
  void initListItems() {
    listItems = [
      new _ListItem(
          bgName: 'assets/images/soso_growth.jpg',
          name: customcintroller.text.toString().isEmpty == false ? customcintroller.text.toString() : "Рост",
          detail: "Нажми, чтобы добавить свой рост"),
      new _ListItem(
          bgName: 'assets/images/soso_weight.jpg',
          name: customcintroller.text.toString().isEmpty == false ? customcintroller.text.toString() :  "Вес",
          detail: "Нажми, чтобы добавить свой вес"),
      new _ListItem(
          bgName: 'assets/images/soso_chest.jpg',
          name: "Грудь",
          detail: "PRO-версия"),
      new _ListItem(
          bgName: 'assets/images/soso_shoulder.jpg',
          name: "Плечи",
          detail: "PRO-версия"),
      new _ListItem(
          bgName: 'assets/images/soso_biceps.jpg',
          name: "Бицепс",
          detail: "PRO-версия")

    ];
  }
}
class _ListItem extends StatelessWidget {
  _ListItem({this.bgName, this.name, this.detail});

  // final int index;
  final String bgName;
  final String name;
  final String detail;
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 180.0,
      margin: const EdgeInsets.symmetric(
        vertical: 1.0,
      ),
      child: new Stack(
        children: <Widget>[
          new Container(
            decoration: new BoxDecoration(
              image: new DecorationImage(
                  image: new AssetImage(bgName),
                  colorFilter: new ColorFilter.mode(
                      Colors.black.withOpacity(0.45), BlendMode.darken),
                  fit: BoxFit.cover,
                  alignment: Alignment.center),
            ),
            child: new SizedBox.expand(
              child: Container(
                alignment: Alignment.center,
                child: new Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  crossAxisAlignment: CrossAxisAlignment.center,
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[
                    new Text(
                      name,
                      style: new TextStyle(fontSize: 29.0, color: Colors.white),
                    ),
                    Padding(
                      padding: const EdgeInsets.only(top: 12.0),
                      child: new Text(
                        detail,
                        style:
                        new TextStyle(fontSize: 16.0, color: Colors.white),
                      ),
                    )
                  ],
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

I expect to get text from alertdialog.

Answer 1

Do you want to update data in your current screen or in another Scaffold/screen? Solution for the first option would be to set your desired data in a setState or pass it to a Model (with ScopedModel) and update the view. E.g. :

FlatButton(
              child: const Text('ОТМЕНА'),
              onPressed: () {
                setState(() {
                   myData = data;
                   Navigator.of(context).pop(); 
                  }); // not sure if this will work, could you try?
            }
            ),

If it is in a new/other screen, you can pass it in the Navigator like for example:

Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => NewScreen(data: myData),
          ),
        );
      },

Does this solve your problem? Otherwise, please elaborate on what it is you need.