A full-fledged Chessboard widget for Flutter. Includes the Chessboard widget, stores game state, and includes a controller to check and manipulate game state.
Full support for formats like PGN, FEN as well as ASCII. Supports multiple colors and displaying arrows on the board. Easy access to making / undoing moves on the board.
Note: v1.0+ is a major refactor and the earlier architecture which used scoped_model
internally
is no longer in use. The ChessBoardController
now stores the state of the game as well as contains
options to change and check state. Arrows on the board are now supported.
Add a ChessBoard
widget and attach a ChessBoardController
to it.
Let's also set the board color and specify the board orientation (default is towards white).
import 'package:flutter/material.dart';
import 'package:flutter_chess_board/flutter_chess_board.dart';
class HomePage extends StatefulWidget {
const HomePage({Key? key}) : super(key: key);
@override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
ChessBoardController controller = ChessBoardController();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Chess Demo'),
),
body: Center(
child: ChessBoard(
controller: controller,
boardColor: BoardColor.orange,
boardOrientation: PlayerColor.white,
),
),
);
}
}
Let's try to display arrows on the board and also display moves of the current game:
import 'package:flutter/material.dart';
import 'package:flutter_chess_board/flutter_chess_board.dart';
class HomePage extends StatefulWidget {
const HomePage({Key? key}) : super(key: key);
@override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
ChessBoardController controller = ChessBoardController();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Chess Demo'),
),
body: Column(
children: [
Expanded(
child: Center(
child: ChessBoard(
controller: controller,
boardColor: BoardColor.orange,
arrows: [
BoardArrow(
from: 'd2',
to: 'd4',
color: Colors.red.withOpacity(0.5),
),
],
boardOrientation: PlayerColor.white,
),
),
),
Expanded(
child: ValueListenableBuilder<Chess>(
valueListenable: controller,
builder: (context, game, _) {
return Text(
controller.getSan().fold(
'',
(previousValue, element) =>
previousValue + '\n' + (element ?? ''),
),
);
},
),
),
],
),
);
}
}
This gives us:
You can listen to game state changes (move, half moves, etc) using either a listener or a ValueListenableBuilder
:
ChessBoardController controller = ChessBoardController();
@override
void initState() {
super.initState();
controller.addListener(() {
// Do something here
});
}
ValueListenableBuilder<Chess>(
valueListenable: controller,
builder: (context, game, _) {
// Build on new game state
},
),
The ChessBoardController
holds the game itself and you can do various kinds of things using it:
controller.loadPgn('demo PGN')
controller.loadFen('demo FEN')
controller.makeMove(from: 'd2', to: 'd4')
controller.undoMove()
controller.isCheckMate()
controller.isDraw()
controller.isStaleMate()
controller.isThreefoldRepetition
...and more...
controller.getMoveCount()
controller.getHalfMoveCount()
To use this package, add chess_board as a dependency in your pubspec.yaml