qt5base-lts/examples/gui/analogclock/main.cpp

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include <QtGui>

#include "rasterwindow.h"

//! [5]
class AnalogClockWindow : public RasterWindow
{
public:
    AnalogClockWindow();

protected:
    void timerEvent(QTimerEvent *) override;
    void render(QPainter *p) override;

private:
    int m_timerId;
};
//! [5]


//! [6]
AnalogClockWindow::AnalogClockWindow()
{
    setTitle("Analog Clock");
    resize(200, 200);

    m_timerId = startTimer(1000);
}
//! [6]

//! [7]
void AnalogClockWindow::timerEvent(QTimerEvent *event)
{
    if (event->timerId() == m_timerId)
        renderLater();
}
//! [7]

//! [1] //! [14]
void AnalogClockWindow::render(QPainter *p)
{
//! [14]
//! [8]
    static const QPoint hourHand[3] = {
        QPoint(7, 8),
        QPoint(-7, 8),
        QPoint(0, -40)
    };
    static const QPoint minuteHand[3] = {
        QPoint(7, 8),
        QPoint(-7, 8),
        QPoint(0, -70)
    };

    QColor hourColor(127, 0, 127);
    QColor minuteColor(0, 127, 127, 191);
//! [8]

//! [9]
    p->setRenderHint(QPainter::Antialiasing);
//! [9] //! [10]
    p->translate(width() / 2, height() / 2);

    int side = qMin(width(), height());
    p->scale(side / 200.0, side / 200.0);
//! [1] //! [10]

//! [11]
    p->setPen(Qt::NoPen);
    p->setBrush(hourColor);
//! [11]

//! [2]
    QTime time = QTime::currentTime();

    p->save();
    p->rotate(30.0 * ((time.hour() + time.minute() / 60.0)));
    p->drawConvexPolygon(hourHand, 3);
    p->restore();
//! [2]

//! [12]
    p->setPen(hourColor);

    for (int i = 0; i < 12; ++i) {
        p->drawLine(88, 0, 96, 0);
        p->rotate(30.0);
    }
//! [12] //! [13]
    p->setPen(Qt::NoPen);
    p->setBrush(minuteColor);
//! [13]

//! [3]
    p->save();
    p->rotate(6.0 * (time.minute() + time.second() / 60.0));
    p->drawConvexPolygon(minuteHand, 3);
    p->restore();
//! [3]

//! [4]
    p->setPen(minuteColor);

    for (int j = 0; j < 60; ++j) {
        if ((j % 5) != 0)
            p->drawLine(92, 0, 96, 0);
        p->rotate(6.0);
    }
//! [4]
}

int main(int argc, char **argv)
{
    QGuiApplication app(argc, argv);

    AnalogClockWindow clock;
    clock.show();

    return app.exec();
}