chasewidget.cpp Example File

webenginewidgets/demobrowser/chasewidget.cpp
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#include "chasewidget.h" #include <QtCore/QPoint> #include <QtWidgets/QApplication> #include <QtGui/QHideEvent> #include <QtGui/QPainter> #include <QtGui/QPaintEvent> #include <QtGui/QShowEvent> ChaseWidget::ChaseWidget(QWidget *parent, QPixmap pixmap, bool pixmapEnabled) : QWidget(parent) , m_segment(0) , m_delay(100) , m_step(40) , m_timerId(-1) , m_animated(false) , m_pixmap(pixmap) , m_pixmapEnabled(pixmapEnabled) { } void ChaseWidget::setAnimated(bool value) { if (m_animated == value) return; m_animated = value; if (m_timerId != -1) { killTimer(m_timerId); m_timerId = -1; } if (m_animated) { m_segment = 0; m_timerId = startTimer(m_delay); } update(); } void ChaseWidget::paintEvent(QPaintEvent *event) { Q_UNUSED(event); QPainter p(this); if (m_pixmapEnabled && !m_pixmap.isNull()) { p.drawPixmap(0, 0, m_pixmap); return; } const int extent = qMin(width() - 8, height() - 8); const int displ = extent / 4; const int ext = extent / 4 - 1; p.setRenderHint(QPainter::Antialiasing, true); if (m_animated) p.setPen(Qt::gray); else p.setPen(QPen(palette().dark().color())); p.translate(width() / 2, height() / 2); // center for (int segment = 0; segment < segmentCount(); ++segment) { p.rotate(QApplication::isRightToLeft() ? m_step : -m_step); if (m_animated) p.setBrush(colorForSegment(segment)); else p.setBrush(palette().background()); p.drawEllipse(QRect(displ, -ext / 2, ext, ext)); } } QSize ChaseWidget::sizeHint() const { return QSize(32, 32); } void ChaseWidget::timerEvent(QTimerEvent *event) { if (event->timerId() == m_timerId) { ++m_segment; update(); } QWidget::timerEvent(event); } QColor ChaseWidget::colorForSegment(int seg) const { int index = ((seg + m_segment) % segmentCount()); int comp = qMax(0, 255 - (index * (255 / segmentCount()))); return QColor(comp, comp, comp, 255); } int ChaseWidget::segmentCount() const { return 360 / m_step; } void ChaseWidget::setPixmapEnabled(bool enable) { m_pixmapEnabled = enable; }