TapHandler: ignore scroll events and native gestures

During a 2-finger press (to emulate right click on a trackpad), the
OS may also generate a QWheelEvent with ScrollBegin phase just in case
scrolling starts.  This must not prematurely deactivate the TapHandler.

Also if a gesture or wheel event begins as the very first event after
an application starts, ensure that subsequent mouse events are not
mis-delivered as wheel or gesture events.

Fixes: QTBUG-71955
Change-Id: Ic12e116483ab9ad37c4ac3b1d10ccb62e1349e0a
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/quick/items/qquickwindow.cpp b/src/quick/items/qquickwindow.cpp
index 83a1268d1d..dd5960e925 100644
--- a/src/quick/items/qquickwindow.cpp
+++ b/src/quick/items/qquickwindow.cpp
@@ -2246,13 +2246,14 @@ QQuickPointerEvent *QQuickWindowPrivate::queryPointerEventInstance(QQuickPointer
 {
     // Search for a matching reusable event object.
     for (QQuickPointerEvent *e : pointerEventInstances) {
-        // If device can generate native gestures (e.g. a trackpad), there might be two QQuickPointerEvents:
-        // QQuickPointerNativeGestureEvent and QQuickPointerTouchEvent.  Use eventType to disambiguate.
+        // If device can generate native gestures (e.g. a trackpad), there might be multiple QQuickPointerEvents:
+        // QQuickPointerNativeGestureEvent, QQuickPointerScrollEvent, and QQuickPointerTouchEvent.
+        // Use eventType to disambiguate.
 #if QT_CONFIG(gestures)
-        if (eventType == QEvent::NativeGesture && !qobject_cast<QQuickPointerNativeGestureEvent*>(e))
+        if ((eventType == QEvent::NativeGesture) != bool(e->asPointerNativeGestureEvent()))
             continue;
 #endif
-        if (eventType == QEvent::Wheel && !qobject_cast<QQuickPointerScrollEvent*>(e))
+        if ((eventType == QEvent::Wheel) != bool(e->asPointerScrollEvent()))
             continue;
         // Otherwise we assume there's only one event type per device.
         // More disambiguation tests might need to be added above if that changes later.