Change QWidget::enterEvent signature to take a QEnterEvent

This is a source incompatible change for widget implementors.
Leaving the old enterEvent as a virtual overload is problematic due to
shadowing. Best to make a clean cut, widget reimplementors will get a compile
time warning if they mark their override as such, or if they try to call the
parent class implementation.

Addresses ### Qt 6 comment.

[ChangeLog][QtWidgets][QWidget] The virtual enterEvent handler now receives
a QEnterEvent, which contains information about mouse position and button
states, rather than a plain QEvent.

Change-Id: I233f594fd79c0c090983b3db8532913d00132fde
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 3 insertions, 5 deletions

diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index dc7f8f7dc4..5a76be82a5 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -8756,7 +8756,7 @@ bool QWidget::event(QEvent *event)
             QCoreApplication::sendEvent(const_cast<QWidget *>(this), &tip);
         }
 #endif
-        enterEvent(event);
+        enterEvent(static_cast<QEnterEvent*>(event));
         break;
 
     case QEvent::Leave:
@@ -9402,7 +9402,7 @@ void QWidget::focusOutEvent(QFocusEvent *)
 }
 
 /*!
-    \fn void QWidget::enterEvent(QEvent *event)
+    \fn void QWidget::enterEvent(QEnterEvent *event)
 
     This event handler can be reimplemented in a subclass to receive
     widget enter events which are passed in the \a event parameter.
@@ -9413,12 +9413,10 @@ void QWidget::focusOutEvent(QFocusEvent *)
     \sa leaveEvent(), mouseMoveEvent(), event()
 */
 
-void QWidget::enterEvent(QEvent *)
+void QWidget::enterEvent(QEnterEvent *)
 {
 }
 
-// ### Qt 6: void QWidget::enterEvent(QEnterEvent *).
-
 /*!
     \fn void QWidget::leaveEvent(QEvent *event)