How to inject synthetised events in Qt5 SceneGraph

[sraboisson]

Hello all,

I'm in Qt5.3.2.
I need to synthetise and inject interaction events (Mouse events, keyboard events, touch events), into a QML Scene (Qt5 scenegraph).
I have a pluggin that correctly receive interaction commands from network, but I can't manage to re-inject those events into the scene graph.
Here is my code for synthetising and injecting events into the scenegraph :

void InteractionInjector::injectMouseEvent(/*BlaBlaBla...*/)
{
    QQuickWindow *lWindow = (QQuickWindow *)QGuiApplication::allWindows().first();
    QQuickItem* lRootItem = lWindow->contentItem();
    
    ...
    
    /*  Recursively send event to all objects in the scenegraph) */
    recurseInjectMouseEvent(lWindow, lRootItem, m_mouseScenePos,
                            (m_mouseButtonState == Pressed)?  QEvent::GraphicsSceneMousePress : 
                                                              QEvent::GraphicsSceneMouseRelease);
}

void InteractionInjector::recurseInjectMouseEvent(QQuickWindow *pWindow, QQuickItem *pRootItem, QPoint pScenePos, QEvent::Type pEvent)
{
    QGraphicsSceneMouseEvent* lEvent;
    bool lResult = false;
    
    lEvent = new QGraphicsSceneMouseEvent(pEvent);
    lEvent->setScenePos(pScenePos);
    lEvent->setButton  (Qt::LeftButton);
    lEvent->setButtons (Qt::LeftButton);
    lEvent->setAccepted(true);
    lResult = pWindow->sendEvent(pRootItem, lEvent);        /*  I always get lResult = false  (why ?)   */
    QApplication::postEvent((QObject*)pRootItem, lEvent);   /*  I also tryed this ....              */

    /*  Recursively iterate through scenegraph hyerarchy  */
    foreach(QQuickItem* lChild, pRootItem->childItems())
    {
        stc_recurseSend(pWindow, lChild, pScenePos, pEvent);
    }
}

In the QML file:

...

    MouseArea {
        anchors.fill: parent
        onPressed:  console.log("MouseArea::onPressed");
        onReleased: console.log("MouseArea::onReleased");
        onClicked:  console.log("MouseArea::onClicked");
    }

I can't manage to get my QML MouseArea's onPressed, onReleased, or onClicked called from my pluggin.
As I mentioned as a comment in the code, I alwas get lResult=false, for all widgets in the scenegraph, but I don't know why ?
Am I doing something wrong ?
Do I really have to parse all the objects in the scenegraph to inject an event, or is there a kind of
"lWindow->getSceneGraph()->sendEvent(...)" somewhere ?

Note: The same kind of code was working in Qt4, but with Qt5 ScenGraph I can't manage to get this functionnality to work again.