Update sceneGrabPosition in MultiPointHandler's points, on grab

We seem to have gotten by without this somehow; but the debug output
in QQuickPinchHandler::handlePointerEventImpl() made it clear that it
wasn't being done: it would always say the points moved from 0,0 to
their present locations.

Change-Id: If611adea6ecf0c056ae7d9b34ca86a7530cfc144
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

2 files changed, 8 insertions, 1 deletions

diff --git a/src/quick/handlers/qquickmultipointhandler.cpp b/src/quick/handlers/qquickmultipointhandler.cpp
index 55a87276fb..85040a1a12 100644
--- a/src/quick/handlers/qquickmultipointhandler.cpp
+++ b/src/quick/handlers/qquickmultipointhandler.cpp
@@ -158,6 +158,13 @@ void QQuickMultiPointHandler::onGrabChanged(QQuickPointerHandler *grabber, QPoin
         return;
     switch (transition) {
     case QPointingDevice::GrabExclusive:
+        for (auto &pt : d->currentPoints)
+            if (pt.id() == point.id()) {
+                pt.m_sceneGrabPosition = point.scenePosition();
+                break;
+            }
+        QQuickPointerHandler::onGrabChanged(grabber, transition, event, point);
+        break;
     case QPointingDevice::GrabPassive:
     case QPointingDevice::UngrabPassive:
     case QPointingDevice::UngrabExclusive:
diff --git a/src/quick/handlers/qquickpinchhandler.cpp b/src/quick/handlers/qquickpinchhandler.cpp
index fffcc2f848..403af14ec8 100644
--- a/src/quick/handlers/qquickpinchhandler.cpp
+++ b/src/quick/handlers/qquickpinchhandler.cpp
@@ -248,11 +248,11 @@ void QQuickPinchHandler::onActiveChanged()
 
 void QQuickPinchHandler::handlePointerEventImpl(QPointerEvent *event)
 {
+    QQuickMultiPointHandler::handlePointerEventImpl(event);
     if (Q_UNLIKELY(lcPinchHandler().isDebugEnabled())) {
         for (const QQuickHandlerPoint &p : currentPoints())
             qCDebug(lcPinchHandler) << Qt::hex << p.id() << p.sceneGrabPosition() << "->" << p.scenePosition();
     }
-    QQuickMultiPointHandler::handlePointerEventImpl(event);
 
     qreal dist = 0;
 #if QT_CONFIG(gestures)