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Simplistic Calculator (#1030)
* Simplistic Calculator, initial commit * Add Linux runner * Add macOS runner, update `main.dart` for iOS * Add a test
This commit is contained in:
Brett Morgan
GitHub
545
simplistic_calculator/lib/main.dart
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545
simplistic_calculator/lib/main.dart
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@@ -0,0 +1,545 @@
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// Copyright 2022 The Flutter team. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import 'dart:io';
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import 'package:auto_size_text/auto_size_text.dart';
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import 'package:flutter/foundation.dart';
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import 'package:flutter/material.dart';
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import 'package:flutter_layout_grid/flutter_layout_grid.dart';
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import 'package:flutter_riverpod/flutter_riverpod.dart';
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import 'package:math_expressions/math_expressions.dart';
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import 'package:window_size/window_size.dart';
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@immutable
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class Display {
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const Display({
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required this.buffer,
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required this.calcHistory,
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required this.mode,
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required this.error,
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});
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final String buffer;
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final List<String> calcHistory;
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final CalculatorEngineMode mode;
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final String error;
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Display copyWith({
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String? buffer,
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List<String>? calcHistory,
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CalculatorEngineMode? mode,
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String? error,
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}) =>
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Display(
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buffer: buffer ?? this.buffer,
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calcHistory: calcHistory ?? this.calcHistory,
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mode: mode ?? this.mode,
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error: error ?? this.error,
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);
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}
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enum CalculatorEngineMode { input, result }
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class CalculatorEngine extends StateNotifier<Display> {
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CalculatorEngine()
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: super(
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const Display(
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buffer: '0',
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calcHistory: [],
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mode: CalculatorEngineMode.result,
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error: '',
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),
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);
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void addToBuffer(String str, {bool continueWithResult = false}) {
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if (state.mode == CalculatorEngineMode.result) {
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state = state.copyWith(
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buffer: (continueWithResult ? state.buffer : '') + str,
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mode: CalculatorEngineMode.input,
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error: '',
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);
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} else {
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state = state.copyWith(
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buffer: state.buffer + str,
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error: '',
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);
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}
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}
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void backspace() {
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final charList = Characters(state.buffer).toList();
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if (charList.isNotEmpty) {
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charList.length = charList.length - 1;
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}
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state = state.copyWith(buffer: charList.join());
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}
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void clear() {
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state = state.copyWith(buffer: '');
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}
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void evaluate() {
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try {
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final parser = Parser();
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final cm = ContextModel();
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final exp = parser.parse(state.buffer);
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final result = exp.evaluate(EvaluationType.REAL, cm) as double;
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if (result.isInfinite) {
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state = state.copyWith(
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error: 'Result is Infinite',
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buffer: '',
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mode: CalculatorEngineMode.result,
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);
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} else if (result.isNaN) {
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state = state.copyWith(
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error: 'Result is Not a Number',
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buffer: '',
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mode: CalculatorEngineMode.result,
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);
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} else {
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if (result.ceil() == result) {
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state = state.copyWith(
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buffer: result.toInt().toString(),
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mode: CalculatorEngineMode.result,
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);
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} else {
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state = state.copyWith(
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buffer: result.toString(),
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mode: CalculatorEngineMode.result,
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);
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}
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}
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} catch (err) {
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state = state.copyWith(
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error: err.toString(),
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buffer: '',
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mode: CalculatorEngineMode.result,
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);
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}
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}
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}
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final displayProvider =
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StateNotifierProvider<CalculatorEngine, Display>((_) => CalculatorEngine());
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void main() {
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setupWindow();
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runApp(
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const ProviderScope(
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child: CalculatorApp(),
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),
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);
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}
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const double kWindowWidth = 600;
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const double kWindowHeight = 900;
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void setupWindow() {
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if (!kIsWeb && (Platform.isWindows || Platform.isLinux || Platform.isMacOS)) {
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WidgetsFlutterBinding.ensureInitialized();
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setWindowTitle('Simplistic Calculator');
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setWindowMinSize(const Size(kWindowWidth, kWindowHeight));
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getCurrentScreen().then((screen) {
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setWindowFrame(
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const Rect.fromLTWH(
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300,
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300,
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kWindowHeight,
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kWindowWidth,
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),
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);
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});
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}
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}
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class CalculatorApp extends ConsumerWidget {
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const CalculatorApp({Key? key}) : super(key: key);
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@override
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Widget build(BuildContext context, WidgetRef ref) {
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final Display display = ref.watch(displayProvider);
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return MaterialApp(
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debugShowCheckedModeBanner: false,
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home: Scaffold(
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body: Container(
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color: Colors.white,
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child: SafeArea(
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child: LayoutGrid(
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areas: '''
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display display display display
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clear bkspc lparen rparen
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sqrt pow abs sgn
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ceil floor e ln
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sin cos tan fact
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arcsin arccos arctan mod
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seven eight nine divide
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four five six multiply
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one two three minus
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zero point equals plus
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''',
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columnSizes: [1.fr, 1.fr, 1.fr, 1.fr],
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rowSizes: [
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2.fr,
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1.fr,
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1.fr,
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1.fr,
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1.fr,
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1.fr,
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2.fr,
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2.fr,
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2.fr,
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2.fr
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],
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children: [
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NamedAreaGridPlacement(
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areaName: 'display',
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child: SizedBox.expand(
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child: Padding(
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padding: const EdgeInsets.symmetric(
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horizontal: 8, vertical: 8),
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child: display.error.isEmpty
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? AutoSizeText(
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display.buffer,
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textAlign: TextAlign.end,
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style: const TextStyle(
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fontSize: 80,
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color: Colors.black,
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),
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maxLines: 2,
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)
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: AutoSizeText(
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display.error,
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textAlign: TextAlign.start,
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style: const TextStyle(
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fontSize: 80,
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color: Colors.red,
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),
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maxLines: 2,
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),
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),
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),
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),
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NamedAreaGridPlacement(
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areaName: 'clear',
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child: CalcButton(
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op: (engine) => engine.clear(),
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label: 'AC',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'bkspc',
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child: CalcButton(
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op: (engine) => engine.backspace(),
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label: '⌫',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'lparen',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('('),
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label: '(',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'rparen',
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child: CalcButton(
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op: (engine) => engine.addToBuffer(')'),
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label: ')',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'sqrt',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('sqrt('),
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label: '√',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'pow',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('^'),
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label: '^',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'abs',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('abs('),
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label: 'Abs',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'sgn',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('sgn('),
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label: 'Sgn',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'ceil',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('ceil('),
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label: 'Ceil',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'floor',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('floor('),
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label: 'Floor',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'e',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('e('),
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label: 'e',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'ln',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('ln('),
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label: 'ln',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'sin',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('sin('),
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label: 'Sin',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'cos',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('cos('),
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label: 'Cos',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'tan',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('tan('),
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label: 'Tan',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'fact',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('!'),
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label: '!',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'arcsin',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('arcsin('),
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label: 'Arc Sin',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'arccos',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('arccos('),
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label: 'Arc Cos',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'arctan',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('arctan('),
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label: 'Arc Tan',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'mod',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('%'),
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label: 'Mod',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'seven',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('7'),
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label: '7',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'eight',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('8'),
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label: '8',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'nine',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('9'),
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label: '9',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'four',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('4'),
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label: '4',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'five',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('5'),
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label: '5',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'six',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('6'),
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label: '6',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'one',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('1'),
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label: '1',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'two',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('2'),
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label: '2',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'three',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('3'),
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label: '3',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'zero',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('0'),
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label: '0',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'point',
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child: CalcButton(
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op: (engine) => engine.addToBuffer('.'),
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label: '.',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'equals',
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child: const CalcEqualsButton(),
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),
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NamedAreaGridPlacement(
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areaName: 'plus',
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child: CalcButton(
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op: (engine) => engine.addToBuffer(
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'+',
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continueWithResult: true,
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),
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label: '+',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'minus',
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child: CalcButton(
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op: (engine) => engine.addToBuffer(
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'-',
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continueWithResult: true,
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),
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label: '-',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'multiply',
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child: CalcButton(
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op: (engine) => engine.addToBuffer(
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'*',
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continueWithResult: true,
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),
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label: '*',
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),
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),
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NamedAreaGridPlacement(
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areaName: 'divide',
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child: CalcButton(
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op: (engine) => engine.addToBuffer(
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'/',
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continueWithResult: true,
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),
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label: '/',
|
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),
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),
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],
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),
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),
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),
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),
|
||||
);
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}
|
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}
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class CalcEqualsButton extends ConsumerWidget {
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const CalcEqualsButton({
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Key? key,
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}) : super(key: key);
|
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|
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@override
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Widget build(BuildContext context, WidgetRef ref) {
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return SizedBox.expand(
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child: Padding(
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padding: const EdgeInsets.all(8.0),
|
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child: ElevatedButton(
|
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onPressed: () => ref.read(displayProvider.notifier).evaluate(),
|
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child: const AutoSizeText(
|
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'=',
|
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style: TextStyle(fontSize: 40, color: Colors.white),
|
||||
),
|
||||
),
|
||||
),
|
||||
);
|
||||
}
|
||||
}
|
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|
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typedef _CalculatorEngineCallback = void Function(CalculatorEngine engine);
|
||||
|
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class CalcButton extends ConsumerWidget {
|
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const CalcButton({
|
||||
Key? key,
|
||||
required this.op,
|
||||
required this.label,
|
||||
}) : super(key: key);
|
||||
|
||||
final _CalculatorEngineCallback op;
|
||||
final String label;
|
||||
|
||||
@override
|
||||
Widget build(BuildContext context, WidgetRef ref) {
|
||||
return SizedBox.expand(
|
||||
child: Padding(
|
||||
padding: const EdgeInsets.all(8.0),
|
||||
child: OutlinedButton(
|
||||
onPressed: () => op(ref.read(displayProvider.notifier)),
|
||||
child: AutoSizeText(
|
||||
label,
|
||||
style: const TextStyle(fontSize: 40, color: Colors.black54),
|
||||
),
|
||||
),
|
||||
),
|
||||
);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user