Qt 5.6 | Qt Widgets | Shaped Clock Example | shapedclock.cpp Example File

Qt 5.6.2 Reference Documentation

# shapedclock.cpp Example File

widgets/shapedclock/shapedclock.cpp

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      #include <QtWidgets>

      #include "shapedclock.h"

      ShapedClock::ShapedClock(QWidget *parent)
          : QWidget(parent, Qt::FramelessWindowHint | Qt::WindowSystemMenuHint)
      {
          QTimer *timer = new QTimer(this);
          connect(timer, SIGNAL(timeout()), this, SLOT(update()));
          timer->start(1000);

          QAction *quitAction = new QAction(tr("E&xit"), this);
          quitAction->setShortcut(tr("Ctrl+Q"));
          connect(quitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
          addAction(quitAction);

          setContextMenuPolicy(Qt::ActionsContextMenu);
          setToolTip(tr("Drag the clock with the left mouse button.\n"
                        "Use the right mouse button to open a context menu."));
          setWindowTitle(tr("Shaped Analog Clock"));
      }

      void ShapedClock::mousePressEvent(QMouseEvent *event)
      {
          if (event->button() == Qt::LeftButton) {
              dragPosition = event->globalPos() - frameGeometry().topLeft();
              event->accept();
          }
      }

      void ShapedClock::mouseMoveEvent(QMouseEvent *event)
      {
          if (event->buttons() & Qt::LeftButton) {
              move(event->globalPos() - dragPosition);
              event->accept();
          }
      }

      void ShapedClock::paintEvent(QPaintEvent *)
      {
          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);

          int side = qMin(width(), height());
          QTime time = QTime::currentTime();

          QPainter painter(this);
          painter.setRenderHint(QPainter::Antialiasing);
          painter.translate(width() / 2, height() / 2);
          painter.scale(side / 200.0, side / 200.0);

          painter.setPen(Qt::NoPen);
          painter.setBrush(hourColor);

          painter.save();
          painter.rotate(30.0 * ((time.hour() + time.minute() / 60.0)));
          painter.drawConvexPolygon(hourHand, 3);
          painter.restore();

          painter.setPen(hourColor);

          for (int i = 0; i < 12; ++i) {
              painter.drawLine(88, 0, 96, 0);
              painter.rotate(30.0);
          }

          painter.setPen(Qt::NoPen);
          painter.setBrush(minuteColor);

          painter.save();
          painter.rotate(6.0 * (time.minute() + time.second() / 60.0));
          painter.drawConvexPolygon(minuteHand, 3);
          painter.restore();

          painter.setPen(minuteColor);

          for (int j = 0; j < 60; ++j) {
              if ((j % 5) != 0)
                  painter.drawLine(92, 0, 96, 0);
              painter.rotate(6.0);
          }
      }

      void ShapedClock::resizeEvent(QResizeEvent * /* event */)
      {
          int side = qMin(width(), height());
          QRegion maskedRegion(width() / 2 - side / 2, height() / 2 - side / 2, side,
                               side, QRegion::Ellipse);
          setMask(maskedRegion);
      }

      QSize ShapedClock::sizeHint() const
      {
          return QSize(100, 100);
      }