grabMouse() and QQWPriv::removeGrabber(): be clear whether mouse or touch

The bug was that a MouseArea could be stuck in pressed state if a touch tap
occurred simultaneously on a second MouseArea while the first was held
pressed by the actual mouse.

QQuickWindowPrivate::setMouseGrabber(QQuickItem *) had too little
information to make the right choice in case the given item argument is
null. It should not mean ungrab everything: in this use case, the mouse and
the touchpoint can be pressing two different MouseAreas, and releasing
either one should ungrab only the MouseArea that is being released.
However the only place it was called with nullptr was in removeGrabber(),
and in that context we are given all the information: which item to ungrab
and whether we want to ungrab mouse, touch or both.  It's better to have
a little code duplication between QQuickItem::grabMouse() and
QQuickWindowPrivate::removeGrabber() than to lose this information
about which device(s) and Item to ungrab.

Task-number: QTBUG-64249
Change-Id: I0710534a05f3ceeb66105a03ab0f32a61df8a522
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

0 files changed, 0 insertions, 0 deletions