// 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. // Flutter code sample for Focus import 'package:flutter/material.dart'; import 'package:flutter/services.dart'; void main() => runApp(const MyApp()); class MyApp extends StatelessWidget { const MyApp({Key? key}) : super(key: key); static const String _title = 'Flutter Code Sample'; @override Widget build(BuildContext context) { return MaterialApp( title: _title, home: Scaffold( appBar: AppBar(title: const Text(_title)), body: const MyStatefulWidget(), ), ); } } class MyStatefulWidget extends StatefulWidget { const MyStatefulWidget({Key? key}) : super(key: key); @override State<MyStatefulWidget> createState() => _MyStatefulWidgetState(); } class _MyStatefulWidgetState extends State<MyStatefulWidget> { 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.headline4!, 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'), ), ), ); }, ), ), ), ); } }