libqt5-qtbase/0002-Synthesize-Enter-LeaveEvent-for-accepted-QTabletEven.patch

From 34db59a076dd824401f952b305a4f575b0140f79 Mon Sep 17 00:00:00 2001
From: Dmitry Kazakov <dimula73@gmail.com>
Date: Mon, 11 Mar 2019 13:18:06 +0300
Subject: [PATCH 2/3] Synthesize Enter/LeaveEvent for accepted QTabletEvent

When the tablet event is accepted, then Qt doesn't synthesize a mouse
event, it means that QApplicationPrivate::sendMouseEvent() will not be
called, and, therefore, enter/leave events will not be dispatched.

The patch looks a bit hackish. Ideally, the synthesize should happen
in QGuiApplicationPrivate::processTabletEvent(), which takes the decision
about synthesizing mouse events. But there is not enough information
on this level: neither qt_last_mouse_receiver nor the receiver widget
are known at this stage.

On Windows and other platforms where there is a parallel stream of
mouse events synthesized by the platform, we shouldn't generate these
events manually.

Change-Id: Ifbad6284483ee282ad129db54606f5d0d9ddd633
---
 src/widgets/kernel/qwidgetwindow.cpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index fbc71cd0ea..729a7f701a 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -1051,6 +1051,18 @@ void QWidgetWindow::handleTabletEvent(QTabletEvent *event)
         event->setAccepted(ev.isAccepted());
     }
 
+    /**
+     * Synthesize Enter/Leave events if it is requested by the system and user
+     */
+    if (widget != qt_last_mouse_receiver &&
+        event->isAccepted() &&
+        !QWindowSystemInterfacePrivate::TabletEvent::platformSynthesizesMouse &&
+        qApp->testAttribute(Qt::AA_SynthesizeMouseForUnhandledTabletEvents)) {
+
+        QApplicationPrivate::dispatchEnterLeave(widget, qt_last_mouse_receiver, event->globalPos());
+        qt_last_mouse_receiver = widget;
+    }
+
     if (event->type() == QEvent::TabletRelease && event->buttons() == Qt::NoButton)
         qt_tablet_target = 0;
 }
-- 
2.21.0