How to read data from Flutter elements

Question

I've the below code for entering some data, I do not know how to handle it!

i.e. What shall I write at the onPressed for the IconButton so that the data is read from all the elements (name, birthday, ...)? and how to display it in Dialog to check if read correctly?

import 'package:flutter/material.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.deepOrange,
      ),
      home: new MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {

  var _value=false;
  double _bodyHeight=0.0;

  void onchange(bool value) {
    setState(() {
      _value = value;
      this._bodyHeight = (value == true) ? 400.0 : 0.0;
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      backgroundColor: Colors.grey[500],
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new SingleChildScrollView(
        child: new Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new Card(
              child: new Container(
                height: 50.0,
                child: new Row(
                  mainAxisAlignment: MainAxisAlignment.end,
                  children: <Widget>[
                    new Text("Select me pls"),
                    new Switch(value: _value, onChanged: (bool value) => onchange(value)),
                  ],
                ),
              ),
            ),
            new Card(
              child: new AnimatedContainer(
                child: new ListView(
                  children: <Widget>[
                      new ListTile(
                      leading: const Icon(Icons.person),
                      title: new TextField(
                        decoration: new InputDecoration(
                          hintText: "Name",
                        ),
                      ),
                    ),
                    new ListTile(
                      leading: const Icon(Icons.phone),
                      title: new TextField(
                        decoration: new InputDecoration(
                          hintText: "Phone",
                        ),
                      ),
                    ),
                    new ListTile(
                      leading: const Icon(Icons.email),
                      title: new TextField(
                        decoration: new InputDecoration(
                          hintText: "Email",
                        ),
                      ),
                    ),
                    const Divider(
                      height: 1.0,
                    ),
                    new ListTile(
                      leading: const Icon(Icons.label),
                      title: const Text('Nick'),
                      subtitle: const Text('None'),
                    ),
                    new ListTile(
                      leading: const Icon(Icons.today),
                      title: const Text('Birthday'),
                      subtitle: const Text('February 20, 1980'),
                    ),
                      new IconButton(icon: const Icon(Icons.save),
                          onPressed: null

                        /* 
                        * 
                        *  What shall I write here to read the data in the elements
                        * 
                        * 
                        * 
                        * */

                      ),
                  ],
                ),
                curve: Curves.easeInOut,
                duration: const Duration(milliseconds: 500),
                height: _bodyHeight,
                // color: Colors.red,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

Answer 1

One way is that TextFields take a property called TextEditingController which allow you to access the value of the TextField.

And to show a dialog you can just call showDialog() function.

class TextFieldExample extends StatefulWidget {
  @override
  _TextFieldExampleState createState() => new _TextFieldExampleState();
}

class _TextFieldExampleState extends State<TextFieldExample> {
  TextEditingController c1;
  TextEditingController c2;
  @override
  void initState() {
      c1 = new TextEditingController();
      c2 = new TextEditingController();
      super.initState();
    }
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      body: new Center(
        child: new Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new TextField (
              controller: c1,
            ),
            new TextField(
              controller: c2,
            ),
            new OutlineButton(onPressed: () {
              showDialog(child: new AlertDialog(
                content: new Text("You entered ${c1.text} ${c2.text} ")
              ),
               context: context

              );
            },
            child: new Text("Show Dialog"),
            )
          ],
        ),
      ),
    );
  }
}