yokutango-mobile-reader/lib/screens/practise/kanji.dart

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:signature/signature.dart';

import '../../models/data_entry.dart';
import '../../components/navigation_buttons.dart';

class KanjiPage extends StatefulWidget {
  final KanjiEntry entry;
  final Function() onNextCard;
  final Function() onPreviousCard;
  final bool showDrawingPanel;
  final bool showStrokeOrder;
  final int? index;

  const KanjiPage({
    required this.entry,
    required this.onNextCard,
    required this.onPreviousCard,
    this.showDrawingPanel = false,
    this.showStrokeOrder = false,
    this.index,
    super.key,
  });

  @override
  _KanjiPageState createState() => _KanjiPageState();
}

class _KanjiPageState extends State<KanjiPage> {
  final focusNode = FocusNode();
  bool isPressed = false;
  late final controller = SignatureController(
    penColor: Theme.of(context).textTheme.bodyMedium?.color ?? Colors.black,
  );

  @override
  void initState() {
    focusNode.requestFocus();
    super.initState();
  }

  @override
  void dispose() {
    focusNode.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return RawKeyboardListener(
      focusNode: focusNode,
      onKey: (event) {
        if (event.isKeyPressed(LogicalKeyboardKey.enter) || event.isKeyPressed(LogicalKeyboardKey.space)) {
          if (widget.showDrawingPanel) return;
          if (isPressed) {
            controller.clear();
            widget.onNextCard();
          }
          setState(() => isPressed = !isPressed);
        }
      },
      child: GestureDetector(
        behavior: HitTestBehavior.opaque,
        onTap: () {
          if (widget.showDrawingPanel) return;
          if (isPressed) {
            controller.clear();
            widget.onNextCard();
          }
          setState(() => isPressed = !isPressed);
        },
        child: Stack(
          alignment: Alignment.center,
          fit: StackFit.expand,
          children: [
            if (widget.showDrawingPanel) ...[
              const SizedBox(width: 20),
              Signature(
                controller: controller,
                backgroundColor: Theme.of(context).scaffoldBackgroundColor,
              )
            ],
            Column(
              crossAxisAlignment: CrossAxisAlignment.center,
              children: [
                Text(
                  widget.entry.kana.join('\n'),
                  style: Theme.of(context).textTheme.headlineMedium,
                ),
                const SizedBox(width: 20),
                const Divider(thickness: 5),
                const SizedBox(width: 20),
                Text(
                  widget.entry.kanji,
                  style: isPressed
                      ? Theme.of(context).textTheme.headlineLarge
                      : Theme.of(context)
                          .textTheme
                          .headlineLarge
                          ?.merge(const TextStyle(color: Colors.transparent)),
                ),
                const SizedBox(width: 20),
                const Divider(thickness: 5),
                if (widget.showDrawingPanel) ...[
                  const SizedBox(width: 20),
                  Row(
                    children: [
                      const Expanded(child: SizedBox()),
                      IconButton(
                        iconSize: 40,
                        onPressed: controller.clear,
                        icon: const Icon(Icons.delete),
                      )
                    ],
                  )
                ]
              ],
            ),
            Positioned(
              bottom: 40,
              child: NavigationButtons(
                middleText:
                    widget.index == null ? 'N' : (widget.index! + 1).toString(),
                onMiddlePressed: () {
                  if (isPressed) {
                    controller.clear();
                    widget.onNextCard();
                  }
                  setState(() => isPressed = !isPressed);
                },
                onNextCard: () => setState(() {
                  if (isPressed) {
                    controller.clear();
                    widget.onNextCard();
                  }
                  setState(() => isPressed = !isPressed);
                }),
                onPreviousCard: () => setState(() {
                  controller.clear();
                  isPressed = false;
                  widget.onPreviousCard();
                }),
              ),
            )
          ],
        ),
      ),
    );
  }
}