Initial commit: Qt Colculator with C++20

.gitignore

@@ -0,0 +1,27 @@
+# Build directories
+build/
+cmake-build-*/
+
+# Qt MOC files
+moc_*.cpp
+moc_*.h
+*.moc
+
+# IDE files
+.idea/
+.vscode/
+*.user
+*.pro.user*
+
+# Executables
+Calculator
+*.exe
+
+# CMake
+CMakeCache.txt
+CMakeFiles/
+cmake_install.cmake
+Makefile
+
+# Debug files
+*.dSYM/

CMakeLists.txt

@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 3.16)
+project(Calculator)
+
+set(CMAKE_CXX_STANDARD 20)
+
+# Добавить флаги для отладки
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -g")
+endif()
+
+find_package(Qt5 REQUIRED COMPONENTS Core Widgets)
+
+set(CMAKE_AUTOMOC ON)
+
+add_executable(Calculator main.cpp
+        Calculator.cpp
+        Calculator.h)
+
+target_link_libraries(Calculator Qt5::Core Qt5::Widgets)

Calculator.cpp

@@ -0,0 +1,154 @@
+#include "Calculator.h"
+#include <QVBoxLayout>
+#include <QGridLayout>
+#include <QString>
+#include <QApplication>
+
+
+    Calculator::Calculator(QWidget *parent) : QWidget(parent)
+    {
+        setupUI(); // Set up the user interface
+        connectSignals(); // Connect signals and slots
+        setWindowTitle("Calculator"); // Set the window title
+        resize(300, 400); // Resize the window to a reasonable size
+    }
+
+    void Calculator::setupUI()
+    {
+        auto *mainLayout = new QVBoxLayout(this);
+
+        //Display setup
+        display = new QLineEdit("0");
+        display -> setReadOnly(true);
+        display -> setAlignment(Qt::AlignRight);
+        display -> setStyleSheet("font-size: 18px; padding: 10px;");
+        mainLayout -> addWidget(display);
+
+        // Button grid
+        auto *gridLayout = new QGridLayout();
+
+        // Clear button
+        clearBtn = new QPushButton("C");
+        gridLayout -> addWidget(clearBtn, 0, 0, 1, 4);
+
+        // Number buttons
+        for (int i = 1; i <= 9; ++i)
+        {
+            auto *btn = new QPushButton(QString::number(i));
+            int row = 3- (i - 1) / 3;
+            int col = (i - 1) % 3;
+            gridLayout -> addWidget(btn, row, col);
+            connect(btn, &QPushButton::clicked, this, &Calculator::digitClicked);
+        }
+
+        //Zero button
+        auto *zeroBtn = new QPushButton("0");
+        gridLayout -> addWidget(zeroBtn, 4, 0, 1, 2);
+        connect(zeroBtn, &QPushButton::clicked, this, &Calculator::digitClicked);
+
+        // Decimal point button
+        auto *dotBtn = new QPushButton(".");
+        gridLayout -> addWidget(dotBtn, 4, 2);
+        connect(dotBtn, &QPushButton::clicked, this, &Calculator::digitClicked);
+
+        // Operator buttons
+        auto *addBtn = new QPushButton("+");
+        auto *subBtn = new QPushButton("-");
+        auto *mulBtn = new QPushButton("*");
+        auto *divBtn = new QPushButton("/");
+        equalBtn = new QPushButton("=");
+
+        gridLayout -> addWidget(divBtn, 1, 3);
+        gridLayout -> addWidget(mulBtn, 2, 3);
+        gridLayout -> addWidget(subBtn, 3, 3);
+        gridLayout -> addWidget(addBtn, 4, 3);
+        gridLayout -> addWidget(equalBtn, 5, 0, 1, 4);
+
+        mainLayout -> addLayout(gridLayout);
+
+        // Store buttons for connections
+        operatorButtons = {addBtn, subBtn, mulBtn, divBtn};
+    }
+
+    void Calculator::connectSignals()
+    {
+        for (auto *btn : operatorButtons)
+        {
+            connect(btn, &QPushButton::clicked, this, &Calculator::operatorClicked);
+        }
+
+        connect(clearBtn, &QPushButton::clicked, this, &Calculator::clearDisplay);
+        connect(equalBtn, &QPushButton::clicked, this, &Calculator::calculateResult);
+    }
+
+    void Calculator::digitClicked()
+    {
+        const auto *button = qobject_cast<QPushButton *>(sender());  // const auto*
+        const QString digit = button -> text();  // const
+
+        if (waitingForOperand) {
+            display -> clear();
+            waitingForOperand = false;
+        }
+
+        if (display -> text() == "0" && digit != ".") {
+            display -> clear();
+        }
+
+        display -> setText(display -> text() + digit);
+    }
+
+    void Calculator::operatorClicked()
+    {
+        auto *button = qobject_cast<QPushButton *>(sender());
+        const QString op = button -> text();
+
+        if (!waitingForOperand && !operation.isEmpty()) {
+            calculateResult();
+        }
+
+        firstNumber = display -> text().toDouble();
+        operation = op;
+        waitingForOperand = true;
+    }
+
+    void Calculator::calculateResult()
+    {
+        if (waitingForOperand || operation.isEmpty()) {
+            return; // No operation to perform
+        }
+
+        double secondNumber = display -> text().toDouble();
+        double result = 0.0;
+
+        if (operation == "+")
+            result = firstNumber + secondNumber;
+        else if (operation == "-")
+            result = firstNumber - secondNumber;
+        else if (operation == "*")
+            result = firstNumber * secondNumber;
+        else if (operation == "/")
+        {
+            if (secondNumber != 0)
+                result = firstNumber / secondNumber;
+            else
+            {
+                display -> setText("Error");
+                clearDisplay();
+                return;
+            }
+        }
+
+        display -> setText(QString::number(result));
+        operation.clear();
+        waitingForOperand = true;
+    }
+
+    void Calculator::clearDisplay()
+    {
+        display -> setText("0");
+        firstNumber = 0.0;
+        operation.clear();
+        waitingForOperand = true;
+    }
+

Calculator.h

@@ -0,0 +1,44 @@
+#ifndef CALCULATOR_H
+#define CALCULATOR_H
+
+#include <QWidget>
+#include <QLineEdit>
+#include <QPushButton>
+#include <QList>
+
+
+class Calculator final : public QWidget{
+    Q_OBJECT
+
+public:
+    explicit Calculator(QWidget *parent = nullptr);
+    ~Calculator() override = default;
+
+    Calculator(const Calculator &) = delete;
+    Calculator &operator=(const Calculator &) = delete;
+    Calculator(Calculator &&) = delete;
+    Calculator &operator=(Calculator &&) = delete;
+
+private slots:
+    void digitClicked();
+    void operatorClicked();
+    void calculateResult();
+    void clearDisplay();
+
+private:
+    void setupUI();
+    void connectSignals();
+
+    QLineEdit *display;
+    QPushButton *clearBtn;
+    QPushButton *equalBtn;
+    QList<QPushButton *> operatorButtons;
+
+    double firstNumber = 0.0;
+    QString operation;
+    bool waitingForOperand = true;
+};
+
+
+
+#endif //CALCULATOR_H

README.md

@@ -0,0 +1,20 @@
+# Qt Calculator
+
+A simple calculator application built with Qt5 and C++20.
+
+## Features
+- Basic arithmetic operations (+, -, *, /)
+- Clear functionality
+- Error handling for division by zero
+- Modern C++ practices (Rule of Five)
+
+## Build Requirements
+- Qt5 (Core, Widgets)
+- CMake 3.16+
+- C++20 compatible compiler
+
+## Building
+```bash
+mkdir build && cd build
+cmake ..
+make

main.cpp

@@ -0,0 +1,13 @@
+#include <QApplication>
+#include "Calculator.h"
+
+
+int main(int argc, char* argv[])
+{
+    QApplication app(argc, argv);
+
+    Calculator calculator;
+    calculator.show();
+
+    return app.exec();
+}