tdf#148699 Qt track the active / shown popup

I have no idea, if there can be multiple active popups in LO in
some way. There can be multiple FloatingWindow and gtk does count
them in m_nFloats... There is a whole lot going on in gtk3 related
to isFloatGrabWindow(), with "funny" comments like:

// FIXME: find out who the hell steals the focus from our frame

So this goes with some "optimistic" approach: there is just one
active popup, so we can track it in QtInstance. It WFM...

Change-Id: I9778587696e1ad9e641dba4f102e2e921266eee6
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/133249
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

vcl/inc/qt5/QtInstance.hxx

@@ -35,6 +35,7 @@
 
 #include "QtFilePicker.hxx"
 
+class QtFrame;
 class QtTimer;
 
 class QApplication;
@@ -67,6 +68,8 @@ class VCLPLUG_QT_PUBLIC QtInstance : public QObject,
     Timer m_aUpdateStyleTimer;
     bool m_bUpdateFonts;
 
+    QtFrame* m_pActivePopup;
+
     DECL_DLLPRIVATE_LINK(updateStyleHdl, Timer*, void);
     void AfterAppInit() override;
 
@@ -177,6 +180,9 @@ public:
 
     bool DoExecute(int& nExitCode) override;
     void DoQuit() override;
+
+    QtFrame* activePopup() const { return m_pActivePopup; }
+    void setActivePopup(QtFrame*);
 };
 
 inline QtInstance* GetQtInstance() { return static_cast<QtInstance*>(GetSalInstance()); }

vcl/inc/qt5/QtWidget.hxx

@@ -73,6 +73,7 @@ class QtWidget : public QWidget
     virtual void paintEvent(QPaintEvent*) override;
     virtual void resizeEvent(QResizeEvent*) override;
     virtual void showEvent(QShowEvent*) override;
+    virtual void hideEvent(QHideEvent*) override;
     virtual void wheelEvent(QWheelEvent*) override;
     virtual void closeEvent(QCloseEvent*) override;
     virtual void changeEvent(QEvent*) override;

vcl/qt5/QtInstance.cxx

@@ -225,6 +225,7 @@ QtInstance::QtInstance(std::unique_ptr<QApplication>& pQApp, bool bUseCairo)
     , m_pQApplication(std::move(pQApp))
     , m_aUpdateStyleTimer("vcl::qt5 m_aUpdateStyleTimer")
     , m_bUpdateFonts(false)
+    , m_pActivePopup(nullptr)
 {
     ImplSVData* pSVData = ImplGetSVData();
     const OUString sToolkit = "qt" + OUString::number(QT_VERSION_MAJOR);
@@ -740,6 +741,12 @@ void QtInstance::DoQuit()
         QApplication::quit();
 }
 
+void QtInstance::setActivePopup(QtFrame* pFrame)
+{
+    assert(!pFrame || pFrame->isPopup());
+    m_pActivePopup = pFrame;
+}
+
 extern "C" {
 VCLPLUG_QT_PUBLIC SalInstance* create_SalInstance()
 {

vcl/qt5/QtWidget.cxx

@@ -316,9 +316,17 @@ void QtWidget::showEvent(QShowEvent*)
     // sequence from QtFrame::SetModal, if the frame was already set visible,
     // resulting in a hidden / unmapped window
     SalPaintEvent aPaintEvt(0, 0, aSize.width(), aSize.height());
+    if (m_rFrame.isPopup())
+        GetQtInstance()->setActivePopup(&m_rFrame);
     m_rFrame.CallCallback(SalEvent::Paint, &aPaintEvt);
 }
 
+void QtWidget::hideEvent(QHideEvent*)
+{
+    if (m_rFrame.isPopup() && GetQtInstance()->activePopup() == &m_rFrame)
+        GetQtInstance()->setActivePopup(nullptr);
+}
+
 void QtWidget::closeEvent(QCloseEvent* /*pEvent*/)
 {
     m_rFrame.CallCallback(SalEvent::Close, nullptr);
@@ -627,11 +635,10 @@ bool QtWidget::handleEvent(QtFrame& rFrame, QWidget& rWidget, QEvent* pEvent)
     }
     else if (pEvent->type() == QEvent::ToolTip)
     {
-        // Qt's POV on focus is wrong for our fake popup windows, so check LO's state.
+        // Qt's POV on the active popup is wrong due to our fake popup, so check LO's state.
         // Otherwise Qt will continue handling ToolTip events from the "parent" window.
-        const vcl::Window* pFocusWin = Application::GetFocusWindow();
-        if (!rFrame.m_aTooltipText.isEmpty() && pFocusWin
-            && pFocusWin->GetFrameWindow() == rFrame.GetWindow())
+        const QtFrame* pPopupFrame = GetQtInstance()->activePopup();
+        if (!rFrame.m_aTooltipText.isEmpty() && (!pPopupFrame || pPopupFrame == &rFrame))
             QToolTip::showText(QCursor::pos(), toQString(rFrame.m_aTooltipText), &rWidget,
                                rFrame.m_aTooltipArea);
         else