A chess board intended to define a custom position
A chess board that is not intended to play chess, but just defined a custom chess position and get its code in Forsyth-Edwards Notation (FEN).
Features
With this widget, you can :
- set value for each cell with a single click (first select the editing piece type / or the trash)
- clear the board / set to the standard position
- load the widget with a custom position and then reset to this initial position when needed
- get the FEN value / set the board from a FEN value The board adjusts itself its layout : either portrait or landscape.
Also, you must define all the labels text manually.
Getting started
- Make sure you give a value to all buttons texts with an instance to the
Labelsclass, - you must create a
PositionControllerby passing the initial position to its constructor : the value of the position in this controller (propertycurrentPosition) will be updated with the latest registered position.
Usage
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key, required this.title});
final String title;
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final _controller = PositionController(
'rnbqkbnr/pp1ppppp/8/2p5/4P3/5N2/PPPP1PPP/RNBQKB1R b KQkq - 1 2');
@override
void initState() {
super.initState();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
children: [
SizedBox(
height: 600.0,
child: EditableChessBoard(
boardSize: 400.0,
controller: _controller,
labels: Labels(
playerTurnLabel: 'Player turn :',
whitePlayerLabel: 'White',
blackPlayerLabel: 'Black',
availableCastlesLabel: 'Available castles :',
whiteOOLabel: 'White O-O',
whiteOOOLabel: 'White O-O-O',
blackOOLabel: 'Black O-O',
blackOOOLabel: 'Black O-O-O',
enPassantLabel: 'En passant square :',
drawHalfMovesCountLabel: 'Draw half moves count : ',
moveNumberLabel: 'Move number : ',
submitFieldLabel: 'Validate field',
currentPositionLabel: 'Current position: ',
copyFenLabel: 'Copy position',
pasteFenLabel: 'Paste position',
resetPosition: 'Reset position',
standardPosition: 'Standard position',
erasePosition: 'Erase position',
),
),
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
ElevatedButton(
onPressed: () {
final isEmptyBoard =
_controller.currentPosition.split(' ')[0] ==
"8/8/8/8/8/8/8/8";
final isValidPosition = !isEmptyBoard &&
chess.Chess.validate_fen(
_controller.currentPosition)['valid'] ==
true;
final message = isValidPosition
? "Valid position"
: "Illegal position !";
final snackBar = SnackBar(
content: Text(message),
);
ScaffoldMessenger.of(context).showSnackBar(snackBar);
},
child: const Text('Validate position'),
),
],
)
],
),
),
);
}
}