Fix enter/leave event generation between native widgets when grabbing.

Removed enter/leave event generation when moving between between
related windows in QWidgetWindow (i.e. native widgets) while some
widget was explicitly grabbing the mouse input. This makes enter/leave
event generation identical to non-native widgets.

Task-number: QTBUG-27551
Change-Id: I4996007bd7922e073a2957ad267a6373e8f3fecc
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index 900818d..b3d46d5 100644 (file)
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -239,9 +239,14 @@ void QWidgetWindow::handleEnterLeaveEvent(QEvent *event)
                 }
             }
         }
-        QWidget *leave = qt_last_mouse_receiver ? qt_last_mouse_receiver.data() : m_widget;
-        QApplicationPrivate::dispatchEnterLeave(enter, leave);
-        qt_last_mouse_receiver = enter;
+        // Enter-leave between sibling widgets is ignored when there is a mousegrabber - this makes
+        // both native and non-native widgets work similarly.
+        // When mousegrabbing, leaves are only generated if leaving the parent window.
+        if (!enter || !QWidget::mouseGrabber()) {
+            QWidget *leave = qt_last_mouse_receiver ? qt_last_mouse_receiver.data() : m_widget;
+            QApplicationPrivate::dispatchEnterLeave(enter, leave);
+            qt_last_mouse_receiver = enter;
+        }
     } else {
         QApplicationPrivate::dispatchEnterLeave(m_widget, 0);
         qt_last_mouse_receiver = m_widget;