Debilitating regression bug in 4.8.x
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https://bugreports.qt-project.org/browse/QTBUG-27043
We rely heavily on QListWidget to have real-live widgets with complex controls as rows. We cannot implement this complex row design with QListView and delegates. T
The effect is there is no scrolling in Mac. Scrollbar has no effects on the viewport. It won't scroll it. Nor will the mouse 'wheel'.
This is a showstopper for us and our Application.
how do we even begin to tackle that?
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Three options:
- Don't use Qt 4.8 while you wait for someone else to fix the problem
- Fix the problem in Qt 4.8 and submit the patch
- Try Qt 5. I don't know, it may be fixed there.
I am, of course, assuming you do not have commercial support.
Alternatively, since you want a vertical scrolling list of widgets, it seems that a QScrollArea with a QWidget container and QVBoxLayout could have a similar function.
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Unfortunately, the problem is still there, even with Qt 5.0.1
It works well in 4.7.4, and unfortunately I had to revert to that version.It's a pity. And yes, I am a commercial customer but nothing from their support yet. I guess they're as puzzled as I am as to why they broke it so many versions ago and never got around to fix this or even relate to the bug report that's sitting there for so long.
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I am happy to report a workaround patch for suggested by Qt-commercial support, applied and seems to be working for my Qt 4.8.5. I'll go post it onto the bug report to help all those who are still struggling. I replaced the "@@" strings in the patch with "^^" for formatting purposes.
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--- /Users/irfanomair/dev/qt-src-carbon-4.8.0/src/gui/kernel/qwidget_mac.mm 2011-12-15 10:38:21.000000000 -0800
+++ kernel/qwidget_mac.mm 2012-09-18 17:17:03.000000000 -0700
^^ -1,22 +1,41 ^^^^ -4684,15 +4703,14 ^^
}// Scroll the whole widget if qscrollRect is not valid:- QRect validScrollRect = qscrollRect.isValid() ? qscrollRect : q->rect();
- validScrollRect &= clipRect();
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QRect validScrollRect = qscrollRect.isValid() ? qscrollRect : QRect(0, 0, q->width(), q->height());
// If q is overlapped by other widgets, we cannot just blit pixels since
// this will move overlapping widgets as well. In case we just update:
const bool overlapped = isOverlapped(validScrollRect.translated(data.crect.topLeft()));
const bool accelerateScroll = accelEnv && isOpaque && !overlapped;
const bool isAlien = (q->internalWinId() == 0);
- const QPoint scrollDelta(dx, dy);
// If qscrollRect is valid, we are _not_ supposed to scroll q's children (as documented). // But we do scroll children (and the whole of q) if qscrollRect is invalid. This case is^^ -4714,7 +4732,6 ^^
}else {
update_sys(qscrollRect);
}-
}return;
#ifdef QT_MAC_USE_COCOA
^^ -4731,6 +4748,7 ^^
// moved when the parent is scrolled. All directly or indirectly moved
// children will receive a move event before the function call returns.
QWidgetList movedChildren;- const QPoint scrollDelta(dx, dy);
if (scrollChildren) {
QObjectList children = q->children();
@