Improve QWheelEvent debug output

We now include the phase, which is helpful, and we distinguish between
modern wheel events with a pixel and/or angle delta, and compatibility
events sent from QWindowSystemInterface::handleWheelEvent with the old
Qt 4 single value delta and orientation.

Change-Id: I2efe9fe7a55c43240ec94bfa70cafaac6d52603c
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/gui/kernel/qevent.cpp b/src/gui/kernel/qevent.cpp
index 2a81cdf385..49f1ba3048 100644
--- a/src/gui/kernel/qevent.cpp
+++ b/src/gui/kernel/qevent.cpp
@@ -4070,7 +4070,12 @@ QDebug operator<<(QDebug dbg, const QEvent *e)
 #  if QT_CONFIG(wheelevent)
     case QEvent::Wheel: {
         const QWheelEvent *we = static_cast<const QWheelEvent *>(e);
-        dbg << "QWheelEvent(" << "pixelDelta=" << we->pixelDelta() << ", angleDelta=" << we->angleDelta() << ')';
+        dbg << "QWheelEvent(" << we->phase();
+        if (!we->pixelDelta().isNull() || !we->angleDelta().isNull())
+            dbg << ", pixelDelta=" << we->pixelDelta() << ", angleDelta=" << we->angleDelta();
+        else if (int qt4Delta = we->delta())
+            dbg << ", delta=" << qt4Delta << ", orientation=" << we->orientation();
+        dbg << ')';
     }
         break;
 #  endif // QT_CONFIG(wheelevent)