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@leonardarnold
Last active June 28, 2019 15:16
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import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
TextEditingController textEditingController = TextEditingController();
final GlobalKey<FormState> _formKey = new GlobalKey<FormState>();
@override
void initState() {
textEditingController.addListener((){
print("controller text : ${textEditingController.text}");
_formKey.currentState.validate();
});
super.initState();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Form(
key: _formKey,
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
TextFormField(
controller: textEditingController,
textAlign: TextAlign.center,
autofocus: true,
style: Theme.of(context).textTheme.headline,
validator: (value) {
print("validator value : $value");
if (!value.contains("hello")) {
return 'validation failed';
}
},
onSaved: (String value) {
//dismiss keyboard
FocusScope.of(context).requestFocus(new FocusNode());
textEditingController.text = "";
},
),
SizedBox(
width: 8,
),
RaisedButton(
child: Text("Save"),
onPressed: () {
if (_formKey.currentState.validate()) {
_formKey.currentState.save();
}
},
)
],
),
)
);
}
}
17:11:48.142 1 info flutter.tools I/flutter (30385): controller text : hel
17:11:48.150 2 info flutter.tools I/flutter (30385): validator value : he
17:11:48.423 3 info flutter.tools I/flutter (30385): controller text : hell
17:11:48.423 4 info flutter.tools I/flutter (30385): validator value : hel
17:11:49.368 5 info flutter.tools I/flutter (30385): controller text : hello
17:11:49.368 6 info flutter.tools I/flutter (30385): validator value : hell
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