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Flutter - State (Text field, Dropdown)

State

To create a text field

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Hello you',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: new HelloYou(),
);
}
}

class HelloYou extends StatefulWidget {
@override
State<StatefulWidget> createState() => new _HelloYouState();
}

class _HelloYouState extends State<HelloYou> {
String name = "";
final _currencies = ['Dollars', 'Euro', 'Pounds'];
String _currency = 'Dollars';
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Hello"),
backgroundColor: Colors.blueAccent,
),
body: Container(
padding: EdgeInsets.all(15.0),
child: Column(
children: <Widget>[
TextField(
decoration: InputDecoration(hintText: 'Please insert a name'),
onChanged: (String string) {
setState(() {
name = string;
});
},
),
DropdownButton<String>(
items: _currencies.map((String value) {
return DropdownMenuItem<String>(
value: value,
child: Text(value),
);
}).toList(),
value: _currency,
onChanged: (String value) {
_onDropDownChange(value);
},
),
Text("Helo " + name)
],
),
),
);
}

void _onDropDownChange(String value) {
setState(() {
this._currency = value;
});
}

}








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