So, situation:
Qt 4.8.4, MSVS 2012.
I have six QToolButton inside QWidget (this QWidget is inside another QWidget ), QToolButtons located in QHBoxLayout.
When I quickly press left mouse button on one of QToolButton, then move mouse out of QToolButton and release mouse button on top parent QWidget 5 or more times. With some probability QToolButton look normal, but in other states(hover, press) it's not repainted.
Searching QTBUG - no result.
QToolButton still emit clicked, pressed, released and else signals, but not repainted.
Some searching in Qt source code and debugging give some information:
I inherit QToolButton, reimlement enterEvent, leaveEvent, mousePressEvent, mouseReleaseEvent, paintEvent.
enterEvent, leaveEvent, mousePressEvent, mouseReleaseEvent - still working.
paintEvent - ignored.
Adding update or repaint in enterEvent, leaveEvent, mousePressEvent, mouseReleaseEvent: no effect.
Then I use break pintsm, and find: in QWidget::repaint(const QRect &rect) checking flags and updatesEnabled() is return false then called return from repaint !!! O_O ok, go inside updatesEnabled().
inline bool QWidget::updatesEnabled() const
{ return !testAttribute(Qt::WA_UpdatesDisabled); }
This is mean Qt::WA_UpdatesDisabled is set true.
Qt Assistant :
Qt::WA_UpdatesDisabled Indicates that updates are blocked (including the system background). This flag is set or cleared by the Qt kernel.
Hmmmmm...
We have another flag Qt::WA_ForceUpdatesDisabled and it we can change:
Indicates that updates are explicitly disabled for the widget; i.e. It will remain disabled even when all its ancestors are set to the updates-enabled state. This implies WA_UpdatesDisabled. This is set/cleared by QWidget::setUpdatesEnabled().
Inside setUpdatesEnabled() attribute Qt::WA_UpdatesDisabled is changing
Using QWidget::setUpdatesEnabled() still has no effect.
I know, this use-case not usual for QToolButton, and I don't try drag and drop. I mean simple sequence: mousePress - mouseMove - mouseRelease.
What some advice?
