blob: f62d5de6eafda149cf6b5091d56be510c40e88a2 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
/// Flutter code sample for [Focus].
void main() => runApp(const FocusExampleApp());
class FocusExampleApp extends StatelessWidget {
const FocusExampleApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(title: const Text('Focus Sample')),
body: const FocusExample(),
),
);
}
}
class FocusExample extends StatefulWidget {
const FocusExample({super.key});
@override
State<FocusExample> createState() => _FocusExampleState();
}
class _FocusExampleState extends State<FocusExample> {
Color _color = Colors.white;
KeyEventResult _handleKeyPress(FocusNode node, RawKeyEvent event) {
if (event is RawKeyDownEvent) {
debugPrint('Focus node ${node.debugLabel} got key event: ${event.logicalKey}');
if (event.logicalKey == LogicalKeyboardKey.keyR) {
debugPrint('Changing color to red.');
setState(() {
_color = Colors.red;
});
return KeyEventResult.handled;
} else if (event.logicalKey == LogicalKeyboardKey.keyG) {
debugPrint('Changing color to green.');
setState(() {
_color = Colors.green;
});
return KeyEventResult.handled;
} else if (event.logicalKey == LogicalKeyboardKey.keyB) {
debugPrint('Changing color to blue.');
setState(() {
_color = Colors.blue;
});
return KeyEventResult.handled;
}
}
return KeyEventResult.ignored;
}
@override
Widget build(BuildContext context) {
final TextTheme textTheme = Theme.of(context).textTheme;
return FocusScope(
debugLabel: 'Scope',
autofocus: true,
child: DefaultTextStyle(
style: textTheme.headlineMedium!,
child: Focus(
onKey: _handleKeyPress,
debugLabel: 'Button',
child: Builder(
builder: (BuildContext context) {
final FocusNode focusNode = Focus.of(context);
final bool hasFocus = focusNode.hasFocus;
return GestureDetector(
onTap: () {
if (hasFocus) {
focusNode.unfocus();
} else {
focusNode.requestFocus();
}
},
child: Center(
child: Container(
width: 400,
height: 100,
alignment: Alignment.center,
color: hasFocus ? _color : Colors.white,
child: Text(hasFocus ? "I'm in color! Press R,G,B!" : 'Press to focus'),
),
),
);
},
),
),
),
);
}
}