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→StatefulWidgetとState
[[File:Flutter_simple_state.png]]
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
final message = "Initial Message.";
@override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Sample',
home: MyPage(message:this.message),
);
}
}
class MyPageState extends State<MyPage>{
String time;
@override
void initState() {
super.initState();
this.time = "Tap Floating Action Button";
}
void showTime(){
setState(() {
this.time = DateTime.now().toString();
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Flutter State Sample'),
),
body: Text(
this.time,
style: TextStyle(fontSize: 32.0),
),
floatingActionButton: FloatingActionButton(
onPressed: showTime,
child: Icon(Icons.timer),
),
);
}
}
class MyPage extends StatefulWidget {
final String message;
MyPage({this.message}):super() {}
@override
State<StatefulWidget> createState() => new MyPageState();
}
[[File:Flutter_simple_state_action.png]]
© 2006 矢木浩人
