Qt 4.8. Tablet Events on Mac OS 10.6.8 - qt

Question

TabletEvents comes as mouse events.
Actual for MAC OS Qt 4.8.0 - 4.8.5.
Works fine in Qt 4.7.3 on any OS and Qt 4.8.0 on Windows and Linux.
I have two instances of QGraphcisScene and two instances of QGraphicsView.
The same types, but one view have a parent, and the another - doesn't (also it's transparent, used for drawing something over desktop).
I'm using tablet (wacom pen and touch) for painting. I handle QTabletEvents and it works only for QGrahicsView instance that doesn't have parent (means parent==0).
On the view with parent (
QMainWindow->centralWidget->ControlContainerWidget->QStackedLayout->QGraphicsView
) tablet events doesn't comes. They comes to QApplication::eventFilter fine, but doesn't comes to view. They comes to QMainWindow as mouseEvents.
If i set parent to 0, tablet events delivers fine.
The 1st receiver of tablet event is QMainWindow.
I see that inside qt_mac_handleTabletEvent:
QWidget *qwidget = [theView qt_qwidget];
QWidget *widgetToGetMouse = qwidget;
And then:
`qt_sendSpontaneousEvent(widgetToGetMouse, &qtabletEvent);`
qtabletEvent - is not accepted event created just before calling sendSpontaneousEvent.
Then inside QApplication::notify():
QWidget *w = static_cast<QWidget *>(receiver);
QTabletEvent *tablet = static_cast<QTabletEvent*>(e);
QPoint relpos = tablet->pos();
bool eventAccepted = tablet->isAccepted();
while (w) {
QTabletEvent te(tablet->type(), relpos, tablet->globalPos(),
tablet->hiResGlobalPos(), tablet->device(), tablet->pointerType(),
tablet->pressure(), tablet->xTilt(), tablet->yTilt(),
tablet->tangentialPressure(), tablet->rotation(), tablet->z(),
tablet->modifiers(), tablet->uniqueId());
te.spont = e->spontaneous();
res = d->notify_helper(w, w == receiver ? tablet : &te);
eventAccepted = ((w == receiver) ? tablet : &te)->isAccepted();
e->spont = false;
if ((res && eventAccepted)
|| w->isWindow()
|| w->testAttribute(Qt::WA_NoMousePropagation))
break;
relpos += w->pos();
w = w->parentWidget();
}
tablet->setAccepted(eventAccepted);
As we can see:
res = d->notify_helper(w, w == receiver ? tablet : &te);
It calls event processing by filters, layouts and then - QMainWindow::tabletEvent. Default implementation is event->ignore().
Since QMainWindow have no Parent, it is all.
So tablet event doesn't comes to QMainWindow childs.
Then seems it is QWidget *qwidget = [theView qt_qwidget]; works wrong.
Unfortunately, i can't debug it...
Please give me some hints... i'm stucked...

Answer 1

I spent more time on comparison Qt 4.8.0 and 4.7.3 and now i see that it is the problem in internal qt event dispatcher. It sends event to NSWindow (QMainWindow) instead of NSView (QGraphicsView).
I didn't found where is the problem, but i found that QMainWindow returns false from ::event() method.
So i reimplemented that method and parsed tablet event there:
bool UBMainWindow::event(QEvent *event)
{
bool bRes = QMainWindow::event(event);
if (NULL != UBApplication::boardController)
{
UBBoardView *controlV = UBApplication::boardController->controlView();
if (controlV && controlV->isVisible())
{
switch (event->type())
{
case QEvent::TabletEnterProximity:
case QEvent::TabletLeaveProximity:
case QEvent::TabletMove:
case QEvent::TabletPress:
case QEvent::TabletRelease:
{
return controlV->directTabletEvent(event);
}
}
}
}
return bRes;
}
The problem is: i need to use tablet for any controls in application, so i need to determine when QGraphicsView is under mouse cursor:
bool UBBoardView::directTabletEvent(QEvent *event)
{
QTabletEvent *tEvent = static_cast<QTabletEvent *>(event);
tEvent = new QTabletEvent(tEvent->type()
, mapFromGlobal(tEvent->pos())
, tEvent->globalPos()
, tEvent->hiResGlobalPos()
, tEvent->device()
, tEvent->pointerType()
, tEvent->pressure()
, tEvent->xTilt()
, tEvent->yTilt()
, tEvent->tangentialPressure()
, tEvent->rotation()
, tEvent->z()
, tEvent->modifiers()
, tEvent->uniqueId());
if (geometry().contains(tEvent->pos()))
{
if (NULL == widgetForTabletEvent(this->parentWidget(), tEvent->pos()))
{
tabletEvent(tEvent);
return true;
}
}
return false;
}
Also i need to stop handle tablet events for QGraphicsView childs.
QWidget *UBBoardView::widgetForTabletEvent(QWidget *w, const QPoint &pos)
{
Q_ASSERT(w);
UBBoardView *board = qobject_cast<UBBoardView *>(w);
QWidget *childAtPos = NULL;
QList<QObject *> childs = w->children();
foreach(QObject *child, childs)
{
QWidget *childWidget = qobject_cast<QWidget *>(child);
if (childWidget)
{
if (childWidget->isVisible() && childWidget->geometry().contains(pos))
{
QWidget *lastChild = widgetForTabletEvent(childWidget, pos);
if (board && board->viewport() == lastChild)
continue;
if (NULL != lastChild)
childAtPos = lastChild;
else
childAtPos = childWidget;
break;
}
else
childAtPos = NULL;
}
}
return childAtPos;
}
Maybe when i will have more time - i will investigate qt more deeply and fix that problem at all.