33c88f86b5 added some logic to QAPM in
order to have it automatically emit headerDataChanged when rows/columns
were added or removed in the model. This was done as a stopgap measure
to prevent QAPM from asking for illegal indices in order to implement
automatic remapping of the section headings (since there's no
mapSectionToSource).
The commit seems to have introduced a regression in QHeaderView, which
isn't prepared to receive headerDataChanged while a row/column count
change is in progress. When receiving headerDataChanged, QHeaderView
will try to read the row/column count and will store it internally.
When it will then receive the signals for insertion/removal of
rows/columns, it will interpret it as a modification of the previously
stored value -- even if the value it stored was already correct.
Fix this by avoiding to have two signals in flight at the same time;
emit headerDataChanged as a queued invocation.
Task-number: QTBUG-114225
Change-Id: I521465a852b8c7135f22f730ead41dca760ba428
Pick-to: 6.5 6.6
Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>
Reviewed-by: David Faure <david.faure@kdab.com>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>