File indexing completed on 2025-04-27 03:58:29

 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2009-04-30
  * Description : Qt item view mouse hover button
  *
  * SPDX-FileCopyrightText: 2008      by Peter Penz <peter dot penz at gmx dot at>
  * SPDX-FileCopyrightText: 2009-2011 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * ============================================================ */
 
 #include "itemviewhoverbutton.h"
 
 // Qt includes
 
 #include <QPainter>
 #include <QPaintEvent>
 #include <QRect>
 #include <QTimer>
 #include <QTimeLine>
 #include <QIcon>
 
 namespace Digikam
 {
 
 ItemViewHoverButton::ItemViewHoverButton(QAbstractItemView* const view)
     : QAbstractButton(view->viewport()),
       m_isHovered       (false),
       m_fadingValue     (0),
       m_icon            (),
       m_fadingTimeLine  (nullptr)
 {
     m_fadingTimeLine = new QTimeLine(600, this);
     m_fadingTimeLine->setFrameRange(0, 255);
 
     setCheckable(true);
     setChecked(false);
 }
 
 void ItemViewHoverButton::setup()
 {
     connect(m_fadingTimeLine, SIGNAL(frameChanged(int)),
             this, SLOT(setFadingValue(int)));
 
     connect(this, SIGNAL(toggled(bool)),
             this, SLOT(refreshIcon()));
 }
 
 void ItemViewHoverButton::initIcon()
 {
     // virtual, cannot call from constructor
 
     refreshIcon();
     resize(sizeHint());
 }
 
 void ItemViewHoverButton::updateToolTip()
 {
 }
 
 void ItemViewHoverButton::reset()
 {
     m_index = QModelIndex();
     hide();
 }
 
 void ItemViewHoverButton::setIndex(const QModelIndex& index)
 {
     m_index = index;
 
     if (index.isValid())
     {
         startFading();
     }
 }
 
 QModelIndex ItemViewHoverButton::index() const
 {
     return m_index;
 }
 
 void ItemViewHoverButton::setVisible(bool visible)
 {
     QAbstractButton::setVisible(visible);
 
     stopFading();
 
     if (visible)
     {
         startFading();
     }
 }
 
 #if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
 
 void ItemViewHoverButton::enterEvent(QEnterEvent* event)
 
 #else
 
 void ItemViewHoverButton::enterEvent(QEvent* event)
 
 #endif
 
 {
     QAbstractButton::enterEvent(event);
 
     // if the mouse cursor is above the button, display
     // it immediately without fading timer
 
     m_isHovered   = true;
     m_fadingTimeLine->stop();
     m_fadingValue = 255;
     updateToolTip();
     update();
 }
 
 void ItemViewHoverButton::leaveEvent(QEvent* event)
 {
     QAbstractButton::leaveEvent(event);
     m_isHovered = false;
     update();
 }
 
 void ItemViewHoverButton::paintEvent(QPaintEvent* event)
 {
     QPainter painter(this);
     painter.setClipRect(event->rect());
     painter.setRenderHint(QPainter::Antialiasing);
 
     // draw an alpha blended circle as background
 
     const QPalette& palette       = parentWidget()->palette();
 
     const QBrush& backgroundBrush = palette.brush(QPalette::Normal, QPalette::Window);
     QColor background             = backgroundBrush.color();
     background.setAlpha(m_fadingValue / 2);
     painter.setBrush(background);
 
     const QBrush& foregroundBrush = palette.brush(QPalette::Normal, QPalette::WindowText);
     QColor foreground             = foregroundBrush.color();
     foreground.setAlpha(m_fadingValue / 4);
     painter.setPen(foreground);
 
     painter.drawEllipse(0, 0, width(), height());
 
     // draw the icon overlay
 
     QPixmap icon = m_icon.pixmap(width() - 2, height() - 2);
 
     if (m_isHovered)
     {
         QPixmap hovered = icon;
         QPainter p(&hovered);
         p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
         p.fillRect(hovered.rect(), QColor(0, 0, 0, 127));
         p.setCompositionMode(QPainter::CompositionMode_Plus);
         p.drawPixmap(0, 0, icon);
         p.end();
         painter.drawPixmap(1, 1, hovered);
     }
     else
     {
         if (m_fadingValue < 255)
         {
             QPainter p(&icon);
             p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
             p.fillRect(icon.rect(), QColor(0, 0, 0, m_fadingValue));
             p.end();
             painter.drawPixmap(1, 1, icon);
         }
         else
         {
             // no fading is required
 
             painter.drawPixmap(1, 1, icon);
         }
     }
 }
 
 void ItemViewHoverButton::setFadingValue(int value)
 {
     m_fadingValue = value;
 
     if (m_fadingValue >= 255)
     {
         m_fadingTimeLine->stop();
     }
 
     update();
 }
 
 /*
 void ItemViewHoverButton::setIconOverlay()
 {
     const char* icon = isChecked() ? "list-remove" : "list-add";
     m_icon = QIcon::fromTheme(icon).pixmap(style()->pixelMetric(QStyle::PM_SmallIconSize));
 }
 */
 
 void ItemViewHoverButton::refreshIcon()
 {
     m_icon = icon();
     update();
 }
 
 void ItemViewHoverButton::startFading()
 {
     if (m_fadingTimeLine->state() != QTimeLine::Running)
     {
         m_fadingTimeLine->start();
     }
 
     m_fadingValue = 0;
 }
 
 void ItemViewHoverButton::stopFading()
 {
     m_fadingTimeLine->stop();
     m_fadingValue = 0;
 }
 
 } // namespace Digikam
 
 #include "moc_itemviewhoverbutton.cpp"