/**************************************************************************** ** ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial Usage ** Licensees holding valid Qt Commercial licenses may use this file in ** accordance with the Qt Commercial License Agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Nokia. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Nokia gives you certain additional ** rights. These rights are described in the Nokia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** If you have questions regarding the use of this file, please contact ** Nokia at qt-info@nokia.com. ** $QT_END_LICENSE$ ** ****************************************************************************/ #ifndef CALCULATOR_H #define CALCULATOR_H #include QT_BEGIN_NAMESPACE class QLineEdit; QT_END_NAMESPACE class Button; class Calculator : public QDialog { Q_OBJECT public: Calculator(QWidget *parent = 0); private slots: void digitClicked(); void unaryOperatorClicked(); void additiveOperatorClicked(); void multiplicativeOperatorClicked(); void equalClicked(); void pointClicked(); void changeSignClicked(); void backspaceClicked(); void clear(); void clearAll(); void clearMemory(); void readMemory(); void setMemory(); void addToMemory(); private: Button *createButton(const QString &text, const char *member); void abortOperation(); bool calculate(double rightOperand, const QString &pendingOperator); double sumInMemory; double sumSoFar; double factorSoFar; QString pendingAdditiveOperator; QString pendingMultiplicativeOperator; bool waitingForOperand; QLineEdit *display; enum { NumDigitButtons = 10 }; Button *digitButtons[NumDigitButtons]; }; #endif #include #include #include "button.h" #include "calculator.h" Calculator::Calculator(QWidget *parent) : QDialog(parent) { sumInMemory = 0.0; sumSoFar = 0.0; factorSoFar = 0.0; waitingForOperand = true; display = new QLineEdit("0"); display->setReadOnly(true); display->setAlignment(Qt::AlignRight); display->setMaxLength(15); QFont font = display->font(); font.setPointSize(font.pointSize() + 8); display->setFont(font); for (int i = 0; i < NumDigitButtons; ++i) { digitButtons[i] = createButton(QString::number(i), SLOT(digitClicked())); } Button *pointButton = createButton(tr("."), SLOT(pointClicked())); Button *changeSignButton = createButton(tr("\261"), SLOT(changeSignClicked())); Button *backspaceButton = createButton(tr("Backspace"), SLOT(backspaceClicked())); Button *clearButton = createButton(tr("Clear"), SLOT(clear())); Button *clearAllButton = createButton(tr("Clear All"), SLOT(clearAll())); Button *clearMemoryButton = createButton(tr("MC"), SLOT(clearMemory())); Button *readMemoryButton = createButton(tr("MR"), SLOT(readMemory())); Button *setMemoryButton = createButton(tr("MS"), SLOT(setMemory())); Button *addToMemoryButton = createButton(tr("M+"), SLOT(addToMemory())); Button *divisionButton = createButton(tr("\367"), SLOT(multiplicativeOperatorClicked())); Button *timesButton = createButton(tr("\327"), SLOT(multiplicativeOperatorClicked())); Button *minusButton = createButton(tr("-"), SLOT(additiveOperatorClicked())); Button *plusButton = createButton(tr("+"), SLOT(additiveOperatorClicked())); Button *squareRootButton = createButton(tr("Sqrt"), SLOT(unaryOperatorClicked())); Button *powerButton = createButton(tr("x\262"), SLOT(unaryOperatorClicked())); Button *reciprocalButton = createButton(tr("1/x"), SLOT(unaryOperatorClicked())); Button *equalButton = createButton(tr("="), SLOT(equalClicked())); QGridLayout *mainLayout = new QGridLayout; mainLayout->setSizeConstraint(QLayout::SetFixedSize); mainLayout->addWidget(display, 0, 0, 1, 6); mainLayout->addWidget(backspaceButton, 1, 0, 1, 2); mainLayout->addWidget(clearButton, 1, 2, 1, 2); mainLayout->addWidget(clearAllButton, 1, 4, 1, 2); mainLayout->addWidget(clearMemoryButton, 2, 0); mainLayout->addWidget(readMemoryButton, 3, 0); mainLayout->addWidget(setMemoryButton, 4, 0); mainLayout->addWidget(addToMemoryButton, 5, 0); for (int i = 1; i < NumDigitButtons; ++i) { int row = ((9 - i) / 3) + 2; int column = ((i - 1) % 3) + 1; mainLayout->addWidget(digitButtons[i], row, column); } mainLayout->addWidget(digitButtons[0], 5, 1); mainLayout->addWidget(pointButton, 5, 2); mainLayout->addWidget(changeSignButton, 5, 3); mainLayout->addWidget(divisionButton, 2, 4); mainLayout->addWidget(timesButton, 3, 4); mainLayout->addWidget(minusButton, 4, 4); mainLayout->addWidget(plusButton, 5, 4); mainLayout->addWidget(squareRootButton, 2, 5); mainLayout->addWidget(powerButton, 3, 5); mainLayout->addWidget(reciprocalButton, 4, 5); mainLayout->addWidget(equalButton, 5, 5); setLayout(mainLayout); setWindowTitle(tr("Calculator")); } void Calculator::digitClicked() { Button *clickedButton = qobject_cast(sender()); int digitValue = clickedButton->text().toInt(); if (display->text() == "0" && digitValue == 0.0) return; if (waitingForOperand) { display->clear(); waitingForOperand = false; } display->setText(display->text() + QString::number(digitValue)); } void Calculator::unaryOperatorClicked() { Button *clickedButton = qobject_cast(sender()); QString clickedOperator = clickedButton->text(); double operand = display->text().toDouble(); double result = 0.0; if (clickedOperator == tr("Sqrt")) { if (operand < 0.0) { abortOperation(); return; } result = sqrt(operand); } else if (clickedOperator == tr("x\262")) { result = pow(operand, 2.0); } else if (clickedOperator == tr("1/x")) { if (operand == 0.0) { abortOperation(); return; } result = 1.0 / operand; } display->setText(QString::number(result)); waitingForOperand = true; } void Calculator::additiveOperatorClicked() { Button *clickedButton = qobject_cast(sender()); QString clickedOperator = clickedButton->text(); double operand = display->text().toDouble(); if (!pendingMultiplicativeOperator.isEmpty()) { if (!calculate(operand, pendingMultiplicativeOperator)) { abortOperation(); return; } display->setText(QString::number(factorSoFar)); operand = factorSoFar; factorSoFar = 0.0; pendingMultiplicativeOperator.clear(); } if (!pendingAdditiveOperator.isEmpty()) { if (!calculate(operand, pendingAdditiveOperator)) { abortOperation(); return; } display->setText(QString::number(sumSoFar)); } else { sumSoFar = operand; } pendingAdditiveOperator = clickedOperator; waitingForOperand = true; } void Calculator::multiplicativeOperatorClicked() { Button *clickedButton = qobject_cast(sender()); QString clickedOperator = clickedButton->text(); double operand = display->text().toDouble(); if (!pendingMultiplicativeOperator.isEmpty()) { if (!calculate(operand, pendingMultiplicativeOperator)) { abortOperation(); return; } display->setText(QString::number(factorSoFar)); } else { factorSoFar = operand; } pendingMultiplicativeOperator = clickedOperator; waitingForOperand = true; } void Calculator::equalClicked() { double operand = display->text().toDouble(); if (!pendingMultiplicativeOperator.isEmpty()) { if (!calculate(operand, pendingMultiplicativeOperator)) { abortOperation(); return; } operand = factorSoFar; factorSoFar = 0.0; pendingMultiplicativeOperator.clear(); } if (!pendingAdditiveOperator.isEmpty()) { if (!calculate(operand, pendingAdditiveOperator)) { abortOperation(); return; } pendingAdditiveOperator.clear(); } else { sumSoFar = operand; } display->setText(QString::number(sumSoFar)); sumSoFar = 0.0; waitingForOperand = true; } void Calculator::pointClicked() { if (waitingForOperand) display->setText("0"); if (!display->text().contains(".")) display->setText(display->text() + tr(".")); waitingForOperand = false; } void Calculator::changeSignClicked() { QString text = display->text(); double value = text.toDouble(); if (value > 0.0) { text.prepend(tr("-")); } else if (value < 0.0) { text.remove(0, 1); } display->setText(text); } void Calculator::backspaceClicked() { if (waitingForOperand) return; QString text = display->text(); text.chop(1); if (text.isEmpty()) { text = "0"; waitingForOperand = true; } display->setText(text); } void Calculator::clear() { if (waitingForOperand) return; display->setText("0"); waitingForOperand = true; } void Calculator::clearAll() { sumSoFar = 0.0; factorSoFar = 0.0; pendingAdditiveOperator.clear(); pendingMultiplicativeOperator.clear(); display->setText("0"); waitingForOperand = true; } void Calculator::clearMemory() { sumInMemory = 0.0; } void Calculator::readMemory() { display->setText(QString::number(sumInMemory)); waitingForOperand = true; } void Calculator::setMemory() { equalClicked(); sumInMemory = display->text().toDouble(); } void Calculator::addToMemory() { equalClicked(); sumInMemory += display->text().toDouble(); } Button *Calculator::createButton(const QString &text, const char *member) { Button *button = new Button(text); connect(button, SIGNAL(clicked()), this, member); return button; } void Calculator::abortOperation() { clearAll(); display->setText(tr("####")); } bool Calculator::calculate(double rightOperand, const QString &pendingOperator) { if (pendingOperator == tr("+")) { sumSoFar += rightOperand; } else if (pendingOperator == tr("-")) { sumSoFar -= rightOperand; } else if (pendingOperator == tr("\327")) { factorSoFar *= rightOperand; } else if (pendingOperator == tr("\367")) { if (rightOperand == 0.0) return false; factorSoFar /= rightOperand; } return true; } #ifndef BUTTON_H #define BUTTON_H #include class Button : public QToolButton { Q_OBJECT public: Button(const QString &text, QWidget *parent = 0); QSize sizeHint() const; }; #endif #include #include "button.h" Button::Button(const QString &text, QWidget *parent) : QToolButton(parent) { setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred); setText(text); } QSize Button::sizeHint() const { QSize size = QToolButton::sizeHint(); size.rheight() += 20; size.rwidth() = qMax(size.width(), size.height()); return size; } #include #include "calculator.h" int main(int argc, char *argv[]) { QApplication app(argc, argv); Calculator calc; calc.show(); return app.exec(); }