This commit replaces qSort with std::sort to fix warnings from compiling with
Qt 5.14.1. Below is one of the warnings:
error: ‘void qSort(RandomAccessIterator, RandomAccessIterator, LessThan) [with RandomAccessIterator = QList<lyx::ColorCode>::iterator; LessT$
an = bool (*)(lyx::ColorCode, lyx::ColorCode)]’ is deprecated: Use std::sort [-Werror=deprecated-declarations]
qSort() has been deprecated since Qt 5.2. Quoting from the ChangeLog [1]:
With STL no longer being optional for building and using Qt, a number of
parts of QtAlgorithms no longer make sense, and have therefore been
deprecated. Replacements are available in the STL, and generally have
much better performance
There are some cases that require more than just a trivial substitution, but
our code does not appear to use any of those cases.
For some discussion on the differences in speed of std::sort() and
qSort(), see the following:
https://phabricator.kde.org/D10857
These are just warnings now, but will likely be errors with Qt 6:
https://bugreports.qt.io/browse/QTBUG-73048
I tested that LyX can still be built against Qt 4.8.7 with this commit.
This commit follows 24926b2e, which also fixes some deprecation warnings.
[1]
https://code.qt.io/cgit/qt/qtbase.git/tree/dist/changes-5.2.0/?h=v5.2.0
These changes fix a few instances of the following type of warning:
error: ‘void QListWidget::setItemSelected(const QListWidgetItem*, bool)’ is deprecated: Use QListWidgetItem::setSelected() instead [-Werror=deprecated-declarations]
as well as similar warnings for setItemHidden() and
setItemExpanded(). These are just warnings now, but it is planned to
remove the methods for Qt 6:
https://bugreports.qt.io/browse/QTBUG-73048
I tested that LyX can still be built against Qt 4.8.7 with this
commit. Indeed, these methods have been deprecated for a while (it
is just that QT_DEPRECATED_WARNINGS was only turned on by default
starting with 5.13.0). See, e.g.,
https://doc.qt.io/archives/qt-4.7/qlistwidget-obsolete.html
In particular, the directory frontends/qt4 is renamed to frontends/qt.
Many configurations file have to be updated. All mentions of qt4 in
the source have been audited, and changed to qt if necessary.
The only part that has not been updated is the CMake build system.
