QCocoaDrag: reset the stored NSView when it gets destroyed

QCocoaDrag stores the last NSView that received an input event, which
becomes a dangling pointer when the NSView gets destroyed. Inform the
QCocoaDrag when NSView's destructor runs, so that it can reset the
pointer (and reset the NSEvent pointer as well) when the destroyed
NSView is the stored one.

With this change alone we'd end up triggering the Q_ASSERT later on in
QCocoaDrag::drag, as m_lastEvent is now nil so the NSWindow will be nil
as well. QCocoaDrag::drag cannot do anything useful if m_lastEvent is
nil, so exit early.

Pick-to: 6.5
Fixes: QTBUG-116554
Change-Id: I5949d728d05adcf3d4a32c91f7e181393bef0422
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
(cherry picked from commit 720ce9b97b767fdf36eaf78107b23bd017e191f3)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
This commit is contained in:
Volker Hilsheimer 2024-11-06 17:29:25 +01:00 committed by Qt Cherry-pick Bot
parent eda1e4b84f
commit a11b0a3d29
3 changed files with 19 additions and 1 deletions

View File

@ -36,6 +36,7 @@ public:
* event and view when handling an event in QNSView
*/
void setLastInputEvent(NSEvent *event, NSView *view);
void viewDestroyed(NSView *view);
void setAcceptedAction(Qt::DropAction act);
void exitDragLoop();

View File

@ -38,6 +38,17 @@ void QCocoaDrag::setLastInputEvent(NSEvent *event, NSView *view)
m_lastView = view;
}
void QCocoaDrag::viewDestroyed(NSView *view)
{
if (view == m_lastView) {
if (m_lastEvent.window.contentView == view) {
[m_lastEvent release];
m_lastEvent = nil;
}
m_lastView = nil;
}
}
QMimeData *QCocoaDrag::dragMimeData()
{
if (m_drag)
@ -95,9 +106,11 @@ Qt::DropAction QCocoaDrag::defaultAction(Qt::DropActions possibleActions,
Qt::DropAction QCocoaDrag::drag(QDrag *o)
{
m_drag = o;
m_executed_drop_action = Qt::IgnoreAction;
if (!m_lastEvent)
return m_executed_drop_action;
m_drag = o;
QMacPasteboard dragBoard(CFStringRef(NSPasteboardNameDrag), QUtiMimeConverter::HandlerScopeFlag::DnD);
m_drag->mimeData()->setData("application/x-qt-mime-type-name"_L1, QByteArray("dummy"));
dragBoard.setMimeData(m_drag->mimeData(), QMacPasteboard::LazyRequest);

View File

@ -173,6 +173,10 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSViewMenuHelper);
[[NSNotificationCenter defaultCenter] removeObserver:self];
[m_mouseMoveHelper release];
// FIXME: Replace with __weak or someting equivalent
QCocoaDrag* nativeDrag = QCocoaIntegration::instance()->drag();
nativeDrag->viewDestroyed(self);
[super dealloc];
}