写一个qt实现计算机的程序，包括头文件和cpp

好的，以下是一个简单的Qt计算器程序的头文件和cpp文件，供您参考：

calculator.h

#ifndef CALCULATOR_H
#define CALCULATOR_H

#include <QWidget>
#include <QLineEdit>
#include <QPushButton>

class Calculator : public QWidget
{
    Q_OBJECT

public:
    Calculator(QWidget *parent = nullptr);

private slots:
    void digitClicked();
    void unaryOperatorClicked();
    void binaryOperatorClicked();
    void equalClicked();
    void pointClicked();
    void changeSignClicked();
    void clearAll();
    void clear();
    void backspace();

private:
    QPushButton *createButton(const QString &text, const char *member);
    void calculate(double rightOperand, const QString &pendingOperator);

    double sumSoFar;
    double factorSoFar;
    QString pendingAdditiveOperator;
    QString pendingMultiplicativeOperator;
    bool waitingForOperand;

    QLineEdit *display;
    QPushButton *digitButtons[10];
    QPushButton *pointButton;
    QPushButton *changeSignButton;
    QPushButton *backspaceButton;
    QPushButton *clearButton;
    QPushButton *clearAllButton;
    QPushButton *divisionButton;
    QPushButton *timesButton;
    QPushButton *minusButton;
    QPushButton *plusButton;
    QPushButton *equalButton;
};

#endif // CALCULATOR_H

calculator.cpp

#include "calculator.h"
#include <QtWidgets>

Calculator::Calculator(QWidget *parent)
    : QWidget(parent), sumSoFar(0.0), factorSoFar(0.0),
      pendingAdditiveOperator(""), pendingMultiplicativeOperator(""), waitingForOperand(true)
{
    display = new QLineEdit("0");
    display->setReadOnly(true);
    display->setAlignment(Qt::AlignRight);
    display->setMaxLength(15);

    for (int i = 0; i < 10; ++i) {
        digitButtons[i] = createButton(QString::number(i), SLOT(digitClicked()));
    }

    pointButton = createButton(".", SLOT(pointClicked()));
    changeSignButton = createButton("\302\261", SLOT(changeSignClicked()));

    backspaceButton = createButton(tr("Backspace"), SLOT(backspace()));
    clearButton = createButton(tr("Clear"), SLOT(clear()));
    clearAllButton = createButton(tr("Clear All"), SLOT(clearAll()));

    divisionButton = createButton(tr("\303\267"), SLOT(unaryOperatorClicked()));
    timesButton = createButton(tr("\303\227"), SLOT(binaryOperatorClicked()));
    minusButton = createButton(tr("-"), SLOT(binaryOperatorClicked()));
    plusButton = createButton(tr("+"), SLOT(binaryOperatorClicked()));
    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);

    for (int i = 1; i < 10; ++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, 1, 2);
    mainLayout->addWidget(pointButton, 5, 3);
    mainLayout->addWidget(changeSignButton, 5, 4);
    mainLayout->addWidget(divisionButton, 2, 5);
    mainLayout->addWidget(timesButton, 3, 5);
    mainLayout->addWidget(minusButton, 4, 5);
    mainLayout->addWidget(plusButton, 5, 5);
    mainLayout->addWidget(equalButton, 6, 5);
    setLayout(mainLayout);

    setWindowTitle(tr("Calculator"));
}

void Calculator::digitClicked()
{
    QPushButton *clickedButton = qobject_cast<QPushButton *>(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()
{
    QPushButton *clickedButton = qobject_cast<QPushButton *>(sender());
    QString clickedOperator = clickedButton->text();
    double operand = display->text().toDouble();
    double result = 0.0;

    if (clickedOperator == tr("Sqrt")) {
        if (operand < 0.0) {
            QMessageBox::warning(this, tr("Calculator"),
                                 tr("Cannot compute the square root of a negative number."));
            return;
        }
        result = std::sqrt(operand);
    } else if (clickedOperator == tr("x\302\262")) {
        result = std::pow(operand, 2.0);
    } else if (clickedOperator == tr("1/x")) {
        if (operand == 0.0) {
            QMessageBox::warning(this, tr("Calculator"),
                                 tr("Cannot divide by zero."));
            return;
        }
        result = 1.0 / operand;
    }
    display->setText(QString::number(result));
    waitingForOperand = true;
}

void Calculator::binaryOperatorClicked()
{
    QPushButton *clickedButton = qobject_cast<QPushButton *>(sender());
    QString clickedOperator = clickedButton->text();
    double operand = display->text().toDouble();

    if (!pendingMultiplicativeOperator.isEmpty()) {
        if (!calculate(operand, pendingMultiplicativeOperator)) {
            return;
        }
        display->setText(QString::number(factorSoFar));
        operand = factorSoFar;
        factorSoFar = 0.0;
        pendingMultiplicativeOperator = "";
    }

    if (!pendingAdditiveOperator.isEmpty()) {
        if (!calculate(operand, pendingAdditiveOperator)) {
            return;
        }
        display->setText(QString::number(sumSoFar));
    } else {
        sumSoFar = operand;
    }

    pendingAdditiveOperator = clickedOperator;
    waitingForOperand = true;
}

void Calculator::equalClicked()
{
    double operand = display->text().toDouble();

    if (!pendingMultiplicativeOperator.isEmpty()) {
        if (!calculate(operand, pendingMultiplicativeOperator)) {
            return;
        }
        operand = factorSoFar;
        factorSoFar = 0.0;
        pendingMultiplicativeOperator = "";
    }

    if (!pendingAdditiveOperator.isEmpty()) {
        if (!calculate(operand, pendingAdditiveOperator)) {
            return;
        }
        pendingAdditiveOperator = "";
    } else {
        sumSoFar = operand;
    }

    display->setText(QString::number(sumSoFar));
    sumSoFar = 0.0;
    waitingForOperand = true;
}

void Calculator::pointClicked()
{
    if (waitingForOperand) {
        display->setText("0");
        waitingForOperand = false;
    }

    if (!display->text().contains('.')) {
        display->setText(display->text() + ".");
    }
}

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::clearAll()
{
    sumSoFar = 0.0;
    factorSoFar = 0.0;
    pendingAdditiveOperator = "";
    pendingMultiplicativeOperator = "";
    display->setText("0");
    waitingForOperand = true;
}

void Calculator::clear()
{
    display->setText("0");
    waitingForOperand = true;
}

void Calculator::backspace()
{
    if (waitingForOperand) {
        return;
    }

    QString text = display->text();
    text.chop(1);
    if (text.isEmpty()) {
        text = "0";
        waitingForOperand = true;
    }
    display->setText(text);
}

QPushButton *Calculator::createButton(const QString &text, const char *member)
{
    QPushButton *button = new QPushButton(text);
    button->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
    connect(button, SIGNAL(clicked()), this, member);
    return button;
}

void Calculator::calculate(double rightOperand, const QString &pendingOperator)
{
    if (pendingOperator == tr("+")) {
        sumSoFar += rightOperand;
    } else if (pendingOperator == tr("-")) {
        sumSoFar -= rightOperand;
    } else if (pendingOperator == tr("\303\227")) {
        factorSoFar = rightOperand;
    } else if (pendingOperator == tr("\303\267")) {
        if (rightOperand == 0.0) {
            QMessageBox::warning(this, tr("Calculator"),
                                 tr("Cannot divide by zero."));
            return;
        }
        factorSoFar /= rightOperand;
    }
}