File indexing completed on 2024-04-28 03:59:02

 /*
     This file is part of the KDE libraries
     SPDX-FileCopyrightText: 1998 Kurt Granroth <granroth@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-only
 */
 
 #include "kcursor.h"
 #include "kcursor_p.h"
 
 #include <QAbstractScrollArea>
 #include <QCursor>
 #include <QEvent>
 #include <QTimer>
 #include <QWidget>
 
 void KCursor::setAutoHideCursor(QWidget *w, bool enable, bool customEventFilter)
 {
     KCursorPrivate::self()->setAutoHideCursor(w, enable, customEventFilter);
 }
 
 void KCursor::autoHideEventFilter(QObject *o, QEvent *e)
 {
     KCursorPrivate::self()->eventFilter(o, e);
 }
 
 void KCursor::setHideCursorDelay(int ms)
 {
     KCursorPrivate::self()->hideCursorDelay = ms;
 }
 
 int KCursor::hideCursorDelay()
 {
     return KCursorPrivate::self()->hideCursorDelay;
 }
 
 // **************************************************************************
 
 KCursorPrivateAutoHideEventFilter::KCursorPrivateAutoHideEventFilter(QWidget *widget)
     : m_widget(widget)
     , m_wasMouseTracking(m_widget->hasMouseTracking())
     , m_isCursorHidden(false)
     , m_isOwnCursor(false)
 {
     mouseWidget()->setMouseTracking(true);
     connect(&m_autoHideTimer, &QTimer::timeout, this, &KCursorPrivateAutoHideEventFilter::hideCursor);
 }
 
 KCursorPrivateAutoHideEventFilter::~KCursorPrivateAutoHideEventFilter()
 {
     if (m_widget != nullptr) {
         mouseWidget()->setMouseTracking(m_wasMouseTracking);
     }
 }
 
 void KCursorPrivateAutoHideEventFilter::resetWidget()
 {
     m_widget = nullptr;
 }
 
 void KCursorPrivateAutoHideEventFilter::hideCursor()
 {
     m_autoHideTimer.stop();
 
     if (m_isCursorHidden) {
         return;
     }
 
     m_isCursorHidden = true;
 
     QWidget *w = mouseWidget();
 
     m_isOwnCursor = w->testAttribute(Qt::WA_SetCursor);
     if (m_isOwnCursor) {
         m_oldCursor = w->cursor();
     }
 
     w->setCursor(QCursor(Qt::BlankCursor));
 }
 
 void KCursorPrivateAutoHideEventFilter::unhideCursor()
 {
     m_autoHideTimer.stop();
 
     if (!m_isCursorHidden) {
         return;
     }
 
     m_isCursorHidden = false;
 
     QWidget *w = mouseWidget();
 
     if (w->cursor().shape() != Qt::BlankCursor) { // someone messed with the cursor already
         return;
     }
 
     if (m_isOwnCursor) {
         w->setCursor(m_oldCursor);
     } else {
         w->unsetCursor();
     }
 }
 
 // The widget which gets mouse events, and that shows the cursor
 // (that is the viewport, for a QAbstractScrollArea)
 QWidget *KCursorPrivateAutoHideEventFilter::mouseWidget() const
 {
     QWidget *w = m_widget;
 
     // Is w a QAbstractScrollArea ? Call setCursor on the viewport in that case.
     QAbstractScrollArea *sv = qobject_cast<QAbstractScrollArea *>(w);
     if (sv) {
         w = sv->viewport();
     }
 
     return w;
 }
 
 bool KCursorPrivateAutoHideEventFilter::eventFilter(QObject *o, QEvent *e)
 {
     Q_UNUSED(o);
     // o is m_widget or its viewport
     // Q_ASSERT( o == m_widget );
 
     switch (e->type()) {
     case QEvent::Leave:
     case QEvent::FocusOut:
     case QEvent::WindowDeactivate:
         unhideCursor();
         break;
     case QEvent::KeyPress:
     case QEvent::ShortcutOverride:
         hideCursor();
         break;
     case QEvent::Enter:
     case QEvent::FocusIn:
     case QEvent::MouseButtonPress:
     case QEvent::MouseButtonRelease:
     case QEvent::MouseButtonDblClick:
     case QEvent::MouseMove:
     case QEvent::Show:
     case QEvent::Hide:
     case QEvent::Wheel:
         unhideCursor();
         if (m_widget->hasFocus()) {
             m_autoHideTimer.setSingleShot(true);
             m_autoHideTimer.start(KCursorPrivate::self()->hideCursorDelay);
         }
         break;
     default:
         break;
     }
 
     return false;
 }
 
 KCursorPrivate *KCursorPrivate::s_self = nullptr;
 
 KCursorPrivate *KCursorPrivate::self()
 {
     if (!s_self) {
         s_self = new KCursorPrivate;
     }
     // WABA: Don't delete KCursorPrivate, it serves no real purpose.
     // Even worse it causes crashes because it seems to get deleted
     // during ~QApplication and ~QApplication doesn't seem to like it
     // when we delete a QCursor. No idea if that is a bug itself.
 
     return s_self;
 }
 
 KCursorPrivate::KCursorPrivate()
 {
     hideCursorDelay = 5000; // 5s default value
     enabled = true;
 }
 
 KCursorPrivate::~KCursorPrivate()
 {
 }
 
 void KCursorPrivate::setAutoHideCursor(QWidget *w, bool enable, bool customEventFilter)
 {
     if (!w || !enabled) {
         return;
     }
 
     QWidget *viewport = nullptr;
     QAbstractScrollArea *sv = qobject_cast<QAbstractScrollArea *>(w);
     if (sv) {
         viewport = sv->viewport();
     }
 
     if (enable) {
         if (m_eventFilters.contains(w)) {
             return;
         }
         KCursorPrivateAutoHideEventFilter *filter = new KCursorPrivateAutoHideEventFilter(w);
         m_eventFilters.insert(w, filter);
         if (viewport) {
             m_eventFilters.insert(viewport, filter);
             connect(viewport, &QObject::destroyed, this, &KCursorPrivate::slotViewportDestroyed);
         }
         if (!customEventFilter) {
             w->installEventFilter(filter); // for key events
             if (viewport) {
                 viewport->installEventFilter(filter); // for mouse events
             }
         }
         connect(w, &QObject::destroyed, this, &KCursorPrivate::slotWidgetDestroyed);
     } else {
         KCursorPrivateAutoHideEventFilter *filter = m_eventFilters.take(w);
         if (filter == nullptr) {
             return;
         }
         w->removeEventFilter(filter);
         if (viewport) {
             m_eventFilters.remove(viewport);
             disconnect(viewport, &QObject::destroyed, this, &KCursorPrivate::slotViewportDestroyed);
             viewport->removeEventFilter(filter);
         }
         delete filter;
         disconnect(w, &QObject::destroyed, this, &KCursorPrivate::slotWidgetDestroyed);
     }
 }
 
 bool KCursorPrivate::eventFilter(QObject *o, QEvent *e)
 {
     if (!enabled || e->type() == QEvent::ChildAdded) {
         return false;
     }
 
     KCursorPrivateAutoHideEventFilter *filter = m_eventFilters.value(o);
 
     Q_ASSERT(filter != nullptr);
     if (filter == nullptr) {
         return false;
     }
 
     return filter->eventFilter(o, e);
 }
 
 void KCursorPrivate::slotViewportDestroyed(QObject *o)
 {
     m_eventFilters.remove(o);
 }
 
 void KCursorPrivate::slotWidgetDestroyed(QObject *o)
 {
     KCursorPrivateAutoHideEventFilter *filter = m_eventFilters.take(o);
 
     Q_ASSERT(filter != nullptr);
 
     filter->resetWidget(); // so that dtor doesn't access it
     delete filter;
 }
 
 #include "moc_kcursor_p.cpp"