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Please review the following information to ensure ** the GNU Free Documentation License version 1.3 requirements ** will be met: http://www.gnu.org/copyleft/fdl.html. ** $QT_END_LICENSE$ ** ****************************************************************************/ /*! \page sourcebreaks.html \title C++ API changes \brief Lists the source incompatible API changes in Qt 5. Qt 5 introduces some source incompatible changes. Here we list some important ones, but you can find more complete lists in \c {/qtbase/dist/changes-5.x.x}. The following sections list the API changes in each module and provide recommendations for handling those changes. \section1 Changes to Qt Core \list \li \l{QLibrary::resolve()} now returns a function pointer instead of \c{void} pointer. \li \c{QLibraryInfo::buildKey()} and the corresponding \c{QT_BUILD_KEY} macro are removed. You must remove all references to this function and macro, as build key is not necessary now. \li The \l{QTranslator::translate()} function signature is changed to set the default value of \c{n} to -1. We recommend you to update the implementation of this virtual function in your sources. \li \c{QBool} is removed. In Qt 4, \l{QString::contains()}, \l{QByteArray::contains()}, and \l{QList::contains()} returned an internal \c{QBool} type so that the Qt3 code \c{if (a.contains() == 2)} would not compile anymore. If your code uses \c{QBool}, replace it with \c{bool}. \li The \c{QUuid::operator QString()} implicit conversion operator is removed. Use the \l{QUuid::toString()} function instead. \li \l{QProcess::ForwardedChannels} no longer forwards the output to the GUI applications on the Windows platform, unless those applications create a console. \li \c{QSystemLocale} is not public anymore. Use \l{QLocale} instead. \li Default value of the \l{QSortFilterProxyModel::dynamicSortFilter} property is changed to \c{true}. \li \c{QTextCodecPlugin} is removed as all the text codecs are part of Qt Core now. \li \c{QFSFileEngine}, \c{QAbstractFileEngine}, \c{QAbstractFileEngineIterator}, and \c{QAbstractFileEngineHandler} are no longer public. We recommend you to avoid using these classes as there is no compatibility promise. \li \l{qDebug()}, \l{qWarning()}, \l{qCritical()}, and \l{qFatal()} are changed to macros now to track the origin of the message in source code. The information to be printed can be configured (for the default message handler) by setting the new \c{QT_MESSAGE_PATTERN} environment variable. \l{qInstallMsgHandler()} is deprecated, so we recommend using \l{qInstallMessageHandler()} instead. \li \l{QPointer} is changed to use \l{QWeakPointer}. The old guard mechanism has been removed, which causes a slight change in behavior when using \l{QPointer}. In earlier Qt versions, if a \l{QPointer} is used on a \l{QWidget} (or a subclass of QWidget), the \l{QPointer} was cleared by the \l{QWidget} destructor. In Qt 5, the \l{QPointer} is cleared by the \l{QObject} destructor along with the \l{QWeakPointer}s. Any \l{QPointer} tracking a widget is not cleared before the \l{QWidget} destructor destroys the children for the widget being tracked. \li \l{Qt::WFlags} is deprecated, use \l{Qt::WindowFlags} instead. This typedef dates from the Qt 1 days, and such abbreviations are not current Qt style. \li \l{Qt::HANDLE} typedef is now defined as \c{void *} on all platforms. \li The non-atomic convenience methods of \l QAtomicInt and \l QAtomicPointer (that is, \c operator=, \c {operator int}, \c {operator T*}, \c operator!, \c operator==, \c operator!=, and \c operator->) have been removed as they performed implicit loads and stores of unspecified memory ordering. Code dealing with loading and storing is expected to use \c load(), \c loadAquire(), \c store(), and \c storeRelease(), instead. \li The return type of \c {QFlags::operator int()} matches the enum's underlying type (signed or unsigned) instead of always being \c int. This allows QFlags over enums of the unsigned type (for example, Qt::MouseButton). \li Because of major changes in the behavior of \l QTextBoundaryFinder::boundaryReasons(), the \c StartWord and \c EndWord enum values were replaced with the \c StartOfItem and \c EndOfItem values to enforce revision of the affected code. \li A number of functions in are deprecated. Use the implementations available in the STL, as described in \l{Porting Guidelines}. \li \c {setSharable()} and \c {isSharable()} in Qt containers are deprecated and will be removed in Qt 6. You should not use them in new applications. If you used them in existing applications, even though they are not documented, you should port away from them. \endlist \section2 Changes to QAction The Softkeys API is removed, so the following functions and enums are removed: \list \li \c QAction::setSoftKeyRole() \li \c QAction::softKeyRole() \li \c QAction::SoftKeyRole \li \c Qt::WA_MergeSoftkeys \li \c Qt::WA_MergeSoftkeysRecursively \li \c Qt::WindowSoftkeysVisibleHint \li \c Qt::WindowSoftkeysRespondHint \endlist \section2 Changes to QChar \list \li \c{QChar::NoCategory} is removed. The \l{QChar::Other_NotAssigned} enum value is returned for unassigned codepoints now. \li \l{QChar::Joining} and \l{QChar::joining()} are deprecated. Use the \l{QChar::JoiningType} enum and \l{QChar::joiningType()} function instead. \endlist \section2 Changes to QCoreApplication \list \li \l{QCoreApplication::translate()} no longer returns the source text if the translation is empty. Use the Qt Linguist Release tool (\c{lrelease -removeidentical}) instead for optimization. \li \c{QCoreApplication::setEventFilter()} and \c{QApplication::x11EventFilter/macEventFilter/qwsEventFilter/winEventFilter} are replaced with \l{QCoreApplication::installNativeEventFilter()} and \l{QCoreApplication::removeNativeEventFilter()} for an API much closer to QEvent filtering. \note The native events that can be filtered this way depend on the \l{Qt Platform Abstraction}{QPA} backend chosen at runtime. On X11, XEvents are replaced with \c{xcb_generic_event_t} due to the switch to XCB, which requires porting the application code to XCB as well. \li \c QCoreApplication::Type and \c QApplication::type() are removed. These Qt 3 legacy application types did not match the application types available in Qt 5. Use \c qobject_cast instead to dynamically find out the exact application type. \li \l{QCoreApplication::hasPendingEvents} and \l{QAbstractEventDispatcher::hasPendingEvents} are deprecated. \endlist \section2 Changes to QEvent \list \li \c{QEvent::AccessibilityPrepare}, \c{QEvent::AccessibilityHelp}, and \c{QEvent::AccessibilityDescription} are removed. \li \l{QEvent::TouchCancel} is introduced to use it on systems where it makes sense to differentiate between a regular \l{QEvent::TouchEnd} and abrupt touch sequence cancellations caused by the compositor. For example, when a swype gesture is recognized. \endlist \section2 Changes to QFile \list \li \l{QFile::setEncodingFunction()} and \l{QFile::setDecodingFunction()} are deprecated. \li \l{QFile::encodeName()} and \l{QFile::decodeName()} are now hard-coded to operate\ on \l{QString::fromLocal8Bit()} and \l{QString::toLocal8Bit()} only. The old behavior is still possible using \l{QTextCodec::setCodecForLocale()}, but the new code should not make assumptions about the file system encoding and older code should remove such assumptions. \endlist \section2 Changes to QFont \list \li \c QFont::handle() is removed. \li \l{QFont::rawName()} and \l{QFont::setRawName()} are deprecated. \endlist \section2 Changes to QMetaType \list \li \c{QMetaType::construct()} is renamed as \l{QMetaType::create()}. \li \c{QMetaType::unregisterType()} is removed. \li \l{QMetaType} now records whether the type argument inherits QObject. Such information can be useful for scripting APIs, so that custom QObject subclasses are treated as QObject pointers. For example, in \l{Qt Script} this means \l{QScriptValue::isQObject()} can be \c true, where it was \c false before. \li \c{QMetaType::QWidgetStar} is removed. Use \l{qMetaTypeId()}{qMetaTypeId()} or \l{QVariant::canConvert()}{QVariant::canConvert()} instead. \li \c{Q_DECLARE_METATYPE(type)} now requires \c{type} to be fully defined. This means, \c{Q_DECLARE_METATYPE(QSharedPointer)} and \c{Q_DECLARE_METATYPE(QWeakPointer)} also need \c{type} to be fully defined. In cases where a forward declared type is needed as a meta-type, use \c{Q_DECLARE_OPAQUE_POINTER(type)}. \endlist \section2 Changes to QMetaMethod \list \li \c{QMetaMethod::signature()} is renamed as \l{QMetaMethod::methodSignature()}, and the return type is changed to \l{QByteArray}. This change is to enable generating the signature string on demand, rather than storing it in the meta-data. \li \l{QMetaMethod::typeName()} no longer returns an empty string if the return type is \c{void}, instead it returns \c{"void"}. The recommended way of checking whether a method returns \c{void} is to compare the return value of \l{QMetaMethod::returnType()} with \l{QMetaType::Void}. \endlist \section2 Changes to QObject \list \li \l{QObject::connectNotify()} and \l {QObject::disconnectNotify()} now need a \l{QMetaMethod} argument that identifies the signal, rather than a \c{const char} pointer. \li \l{QObject::trUtf8()} and \c{QCoreApplication::Encoding} are deprecated. Qt assumes that the source code is encoded in UTF-8. \endlist \section2 Changes to QVariant \list \li The \l{QVariant} constructor which takes \l{Qt::GlobalColor} argument is removed. Code constructing such variants must explicitly call \l{QColor} constructor now. For example, instead of \c{QVariant(Qt::red)}, use \c{QVariant(QColor(Qt::red))} to create a \l{QVariant} instance. \li Implicit creation of QVariant objects from the enum values Qt::BrushStyle, Qt::PenStyle, and Qt::CursorShape has been removed. Create objects explicitly or use \c static_cast(Qt::SolidLine) to create a QVariant of type \c int with the same value as the enum. \endlist \section2 Changes to QAbstractEventDispatcher \list \li The signature for the pure-virtual \c{registerTimer()} function is changed. All subclasses of \l{QAbstractEventDispatcher} must re-implement the function with this new signature: \code virtual void registerTimer(int timerId, int interval,Qt::TimerType timerType, QObject *object) = 0; \endcode \li QAbstractEventDispatcher::TimerInfo is no longer a \c{typedef} of \c{QPair}. It is now a \c{struct} with 3 members: \c{int timerId}, \c{int interval}, and \c{Qt::TimerType timerType}. Update the \l{QAbstractEventDispatcher::registeredTimers()} function with this change. \endlist \section2 Changes to QDir \list \li The \c{convertSeparators()} function is removed. Use \l{QDir::toNativeSeparators()} instead. \li The \c{QDir::NoDotAndDotDot} enum value is removed. Use \l{QDir::NoDot} or \l{QDir::NoDotDot} instead. \endlist \section2 Changes to QLocale \list \li The QLocale data has been updated to CLDR 22.1. The historical language and country names were updated to their modern values and some deprecated names were dropped or mapped to their modern alternatives. \li The \l{QLocale::toShort()}, \l{QLocale::toUShort()}, \l{QLocale::toInt()}, \l{QLocale::toUInt()}, \l{QLocale::toLongLong()}, and \l{QLocale::toULongLong()} functions no longer take the argument for base. They localize base 10 conversions. To convert other bases, use the \l{QString} functions instead. \endlist \section2 Changes to QAbstractItemModel \list \li \l{QAbstractItemModel::beginMoveRows()} no longer emits the \c{layoutAboutToBeChanged} signal, and \l{QAbstractItemModel::endMoveRows()} no longer emits the \c{layoutChanged} signal. All proxy models must connect to (and disconnect from) the \l{QAbstractItemModel::rowsAboutToBeMoved} and \l{QAbstractItemModel::rowsMoved} signals. \li \l{QAbstractItemModel::sibling()} is virtual now to allow implementations to optimize based on internal data. \li \l{QAbstractItemModel::createIndex()} method now only provides the \c void* and \c quintptr overloads, making calls with a literal \c 0 (\c{createIndex(row, col, 0)}) ambiguous. Either cast \c{quintptr(0)} or omit the third argument to get the \c void* overload. \li \l{QAbstractItemModel::setRoleNames()} is deprecated. Use \l{QAbstractItemModel::roleNames()} instead. \l{QAbstractItemModel::roleNames()} is virtual now to allow a consistent API with the rest of QAbstractItemModel. Reimplementing the virtual methods to provide the elements is preferred to setting those directly. \endlist \section2 Changes to QString \list \li \l{QString} and \l{QByteArray} constructors now use a negative size to indicate that the string passed is null-terminated (a null-terminated array of \l{QChar}, in the case of QString). In Qt 4, negative sizes were ignored, which resulted in empty \l{QString} and \l{QByteArray}. The size argument now has a default value of \c -1, replacing the separate constructors that did the same. \li \l{QString::mid()}, \l{QString::midRef()}, and \l{QByteArray::mid()} now return an empty \c{QString}, \c{QStringRef}, and \c{QByteArray} respectively, if the position passed is equal to the length (that is, right after the last character or byte). In Qt 4, they returned a null \c{QString} or a null \c{QStringRef}. \li The following \l{QString} functions use the C locale instead of the default or system locale: \list \li \l{QString::toLongLong()}{toLongLong()} \li \l{QString::toULongLong()}{toULongLong()} \li \l{QString::toLong()}{toLong()} \li \l{QString::toULong()}{toULong()} \li \l{QString::toInt()}{toInt()} \li \l{QString::toUInt()}{toUInt()} \li \l{QString::toShort()}{toShort()} \li \l{QString::toUShort()}{toUShort()} \li \l{QString::toDouble()}{toDouble()} \li \l{QString::toFloat()}{toFloat()} \endlist This is to guarantee consistent default conversion of strings. For locale-aware conversions use the equivalent \l{QLocale} functions. \endlist \section2 Changes to QDate, QTime, and QDateTime \list \li QDate only implements the Gregorian calendar, and the switch to the Julian calendar before 1582 has been removed. This means all QDate functions return different results for dates prior to 15 October 1582, and there is no longer a gap between 4 October 1582 and 15 October 1582. \li \l{QDate::setYMD()} is deprecated, use \l{QDate::setDate()} instead. \li Adding days to a null QDate or seconds to a null QTime will no longer return a valid QDate/QTime. \li The \l{QDate::addDays()} and QDateTime::addDays() functions now take a \c{qint64} argument, and the \l{QDate::daysTo()} and \l{QDateTime::daysTo()} functions now return a \c{qint64} value. \li \l QDate and \l QTime are the \c userProperty for the \l QTimeEdit and \l QDateEdit classes, insted of QDateTime as it was for the 4.7 and 4.8 releases. The USER property for these classes was removed before Qt 4.7.0 and added again in Qt 5.0. \li The serialization behavior for \l QDateTime is reverted to pre-Qt 5, because \l Qt::LocalTime is the local time (that is, \c {ymd hms}) regardless of the underlying system time, time zone, or changes in the system zone. Therefore, the consistent behavior when serialising is to save and restore as the local time and not its UTC equivalent. This means that the \l QDataStream version is 14 since Qt 5.1. \li The supported date range in \l QDateTime has been reduced to about +/- 292 million years, the range supported by the number of msecs since the Unix epoch of 1 Jan 1970 as stored in a \c qint64, and as able to be used in \l{QDateTime::setMSecsSinceEpoch()} and \l{QDateTime::toMSecsSinceEpoch()}. \li \l{QDate::fromString()} and \l{QDateTime::fromString()} require non-numeric date component separators when parsing \l{Qt::ISODate}. A string like \e 2000901901 will no longer be recognized as a valid ISO date, whereas \e 2000/01/01 will, even though it differs from the ISO format \e 2000-01-01. \endlist \section2 Changes to QTextCodec \list \li \c{QTextCodec::codecForCStrings()} and \c{QTextCodec::setCodecForCStrings()} are removed as they were creating uncertainty/bugs in using QString easily and (to a lesser extent) performance issues. \li \c{QTextCodec::codecForTr()} and \c{QTextCodec::setCodecForTr()} are removed. \endlist \section2 Changes to QUrl \l{QUrl} changed considerably in Qt 5 to comply better with the URL specifications and with brokenness out there. The following list summarizes the most important functional changes: \list \li \l{QUrl::setPath()} no longer handles relative paths. They are by definition invalid. Use the \l{QUrl::NormalizePathSegments} flag to remove /./ or /../ sequences as much as possible. It will not remove /../ from the beginning of the path. \li \l{QUrl} has been changed to operate only on percent-encoded forms. Fully-decoded forms where the percent character stands for itself, can no longer be encoded, as the getters and setters with \e encoded in the name are deprecated (except \l{QUrl::toEncoded()} and \l{QUrl::fromEncoded()}). The most notable difference with this change is when dealing with \l{QUrl::toString()}. In earlier Qt versions, this function would return percent characters in the URL, but now it returns \e %25 like \l{QUrl::toEncoded()} does. \li \l{QUrl} no longer decodes %7B and %7D to "{" and "}" in the output of \l{QUrl::toString()}. \li \l{QUrl} now defaults to decoded mode in the getters and setters for \c userName, \c password, \c host, \c topLevelDomain, \c path and \c fileName. This means a % in one of those fields is now returned (or set) as \c % rather than \c %25. If the former behavior was expected, pass \c PrettyDecoded to the getter and \c TolerantMode to the setter. \li \l{QUrl} no longer has functions that handle individual query items and query delimiters, such as \c addQueryItem() and \c queryPairDelimiter(). These have been moved to the new \l{QUrlQuery} class. \li \l{QUrl} no longer considers all delimiter characters equivalent to their percent-encoded forms. \l{QUrl} and \l{QUrlQuery} always keep all delimiters exactly as they were in the original URL text. \li \l{QUrl} no longer supports \l{QUrl::FullyDecoded} mode in \l{QUrl::authority()} and \l{QUrl::userInfo()}, nor \l{QUrl::DecodedMode} in \l{QUrl::setAuthority()} and \l{QUrl::setUserInfo()}. \li \l{QUrl} no longer decodes %23 found in the fragment to "#" in the output of \l{QUrl::toString} (\c FullyEncoded) or \l{QUrl::toEncoded()}. \endlist \section1 Changes to Qt Concurrent \l{Qt Concurrent} has been moved from \l {Qt Core} to its own module. To link against the Qt Core module, add this line to the project file: \code QT += concurrent \endcode \note The \c {QtConcurrent::Exception} class is renamed \l{QException} and \c {QtConcurrent::UnhandledException} class is renamed \l{QUnhandledException}. They remain in Qt Core. \section1 Changes to Qt GUI \list \li \l{QPen} now has a default width of 1 instead of 0. Thus, it is no longer \l{QPen::isCosmetic()}{cosmetic} by default. \li \l{QAccessibleActionInterface} is now based on providing a list of action names. All functions have been changed to take arguments of type \c string insted of \c{int}. \li The constructor of \l{QAccessibleEvent} does not need the \c{child} parameter anymore, and the corresponding \c{QAccessibleEvent::child()} function is removed. \li The constructor of \l{QTabletEvent} does not need the \c{hiResGlobalPos} argument anymore, as all coordinates are floating point-based now. \li \c{QIconEngineV2} is now merged into \l{QIconEngine}. Update your sources to use \c{QIconEngine} instead of \c{QIconEngineV2}. \li \l{QSound} is moved to Qt Multimedia from Qt GUI. \li \c QDesktopServices::storageLocation() and \c QDesktopServices::displayName() are replaced by \l{QStandardPaths::writableLocation()} and \l{QStandardPaths::displayName()} respectively. They are now in the \l{Qt Core} module. Make sure to read the \l{QDesktopServices::storageLocation()} documentation when porting from \l{QDesktopServices::DataLocation}. \li \c QPixmap::grabWindow() and \c QPixmap::grabWidget() are removed. Use \l{QScreen::grabWindow()} instead. \li The session management API has been simplified. The \c commitData() function is removed and replaced by the signal \l{QGuiApplication::commitDataRequest()}. \l QApplication and \l QGuiApplication will emit this signal from 5.2 onward on supported platforms (Linux and Windows). \li \c{QWidget *widget()} is replaced with \c {QObject *target()} to avoid \l{QWidget} dependencies. \endlist \section2 Changes to QAccessibleInterface \list \li The \e child integer parameters are removed to bring \l{QAccessibleInterface} closer to IAccessible2. This means that the following functions lose the integer parameter: \list \li \c{text(Text t, int child)} is now \l{QAccessibleInterface::text()}{text(Text t)} \li \c{rect(int child)} is now \l{QAccessibleInterface::rect()}{rect()} \li \c{setText(Text t, int child, const QString &text)} is now \l{QAccessibleInterface::setText()}{setText(Text t, const QString &text)} \li \c{role(int child)} is now \l{QAccessibleInterface::role()} {role()} \li \c{state(int child)} is now \l{QAccessibleInterface::state()}{state()} \endlist \li \c{navigate()} is replaced with \l{QAccessibleInterface::parent()} {parent()} and \l{QAccessibleInterface::child()}{child()} to navigate the hierarchy. \li \c{relationTo()} is replaced with \l{QAccessibleInterface::relations()}{relations()}. \li \c{QAccessibleInterface::userActionCount()}, \c{QAccessibleInterface::actionText()}, and \c{QAccessibleInterface::doAction()} are removed. We recommend using the \l{QAccessibleInterface} subclasses to implement the \l{QAccessibleActionInterface} instead. \endlist \section2 Changes to QImage \list \li \l{QImage::fill()} on an image with format \c{Format_RGB888} now expects image data in RGB layout as opposed to BGR layout. This is to ensure consistency with RGB32 and other 32-bit formats. \li The behavior of \l{QImage::load()}, \l{QImage::loadFromData()}, \l{QPixmap::load()}, and \l{QPixmap::loadFromData()} on a non-null image changed so that if the functions fail to load the image (return \c false), the the existent image data is invalidated, so that \c isNull() is guaranteed to return \c true in this case. \endlist \section2 Changes to QPainter \list \li \l{QPainter} does not support uniting clipped regions anymore. Use \l{QRegion::united()} instead to unite clips and pass the result to \l{QPainter}. \li \l{QPainter} fill rules when not using antialiased painting have changed so that the aliased and antialiased coordinate systems match. There used to be an offset of slightly less than half a pixel when doing sub-pixel rendering, in order to be consistent with the old X11 paint engine. The new behavior should be more predictable and give the same consistent rounding for images and pixmaps as for paths and rectangle filling. To get the old behavior, set the \l{QPainter::Qt4CompatiblePainting} render hint. \endlist \section2 Changes to QTouchEvent \list \li \l{QTouchEvent::DeviceType} and \l{QTouchEvent::deviceType()} are deprecated as \l{QTouchDevice} provides a better way to identify and access the device from which the events originate. \li The constructor now takes a \l{QTouchDevice} pointer instead of \c{DeviceType} value. \li \c TouchPointStateMask and \c TouchPointPrimary are removed from the \l{Qt::TouchPointStates} enum. \li \c{QTouchEvent::TouchPoint::isPrimary()} is removed. \endlist \section1 Changes to Qt Widgets \list \li \l{QItemEditorFactory::createEditor()} and \l{QItemEditorFactory::valuePropertyName()} signatures are changed to take arguments of type \c{int} instead of \l{QVariant::Type}. \li \c{QInputContext} is removed as related getter and setter functions in \l{QWidget} and \l{QApplication} are removed. Input contexts are now platform-specific. \li \l{QInputDialog::getInteger()} is deprecated. Use \l{QInputDialog::getInt()} instead. \li The \c{QStyleOption*V{2,3,4}} classes are removed, and their members are merged with the respective base classes. The removed classes are left as typedefs for binary compatibility. \li \l{QGraphicsItem} and its derived classes can no longer pass a \l{QGraphicsScene} to the item's constructor. Construct the item without a scene and call \l{QGraphicsScene::addItem()} to add the item to the scene. \li \c{QProxyModel} is removed. Use \l{QAbstractProxyModel} and the related classes instead. A copy of \c{QProxyModel} is available in the \l{http://qt-project.org/wiki/Qt-5-UI-Helpers}{Ui Helpers} repository. \endlist \section2 Changes to QApplication \list \li \c QApplication::setGraphicsSystem() is removed, because the introduction of \l{Qt Platform Abstraction}{QPA} made it redundant. \li \c{QApplication::commitData} and \c{QApplication::saveState} virtual methods that were used for session management are removed. Connect to the \l{QApplication::commitDataRequest} and \l{QApplication::saveStateRequest} signals instead. Use \l{QApplication::isSavingSession()} if the \l{QWidget::closeEvent} if your window needs to know whether it is being called during shutdown. \endlist \section2 Changes to QStyle \list \li \c{QStyle::standardIconImplementation()} and \c{QStyle::layoutSpacingImplementation()} are removed, and the \l{QStyle::standardIcon()} and \l{QStyle::layoutSpacing()} functions are made pure virtual now. The removed functions were introduced in Qt 4 for binary compatibility reasons. \li \c QMotifStyle, \c QPlastiqueStyle, \c QCleanlooksStyle, and \c QCDEStyle are replaced with a new \e fusion style. If your application depends on any of these removed styles, you can either use the \l{http://qt.gitorious.org/qt/qtstyleplugins}{qtstyleplugins} project to get these styles or update your application to use the new fusion style. For more details about this change, see \l{https://blog.qt.digia.com/blog/2012/10/30/cleaning-up-styles-in-qt5-and-adding-fusion/}. \li The following QStyle implementations have been made internal: \list \li QFusionStyle \li QGtkStyle \li QMacStyle \li QWindowsCEStyle \li QWindowsMobileStyle \li QWindowsStyle \li QWindowsVistaStyle \li QWindowsXPStyle \endlist Instead of creating instances or inheriting these classes directly, use: \list \li QStyleFactory for creating instances of specific styles. \li QProxyStyle for customizing existing style implementations. \li QCommonStyle as a base for implementing full custom styles. \endlist \endlist \section2 Changes to QHeaderView The following functions are deprecated: \list \li \c{void setMovable(bool movable)} - Use \l{QHeaderView::setSectionsMovable()} instead. \li \c{bool isMovable() const} - Use \l{QHeaderView::sectionsMovable()} instead. \li \c{void setClickable(bool clickable)} - Use \l{QHeaderView::setSectionsClickable()} instead. \li \c{bool isClickable() const} - Use \l{QHeaderView::sectionsClickable()} instead. \li \c{void setResizeMode(int logicalindex, ResizeMode mode)} - Use \l{QHeaderView::setSectionResizeMode()} instead. \li \c{ResizeMode resizeMode(int logicalindex) const} - Use \l{QHeaderView::sectionResizeMode()} instead. \endlist \section2 Changes to QAbstractItemView \list \li The derived classes now emit the \c{clicked()} signal on the left mouse click only, instead of all mouse clicks. \li The virtual \l{QAbstractItemView::dataChanged()} function signature now includes the roles that have changed. The signature is consistent with the \c{dataChanged()} signal in the model. \endlist \section2 Changes to QColorDialog \list \li \l{QColorDialog::customColor()} now returns a \l{QColor} value instead of \c{QRgb}. \li \l{QColorDialog::setCustomColor()} and \l{QColorDialog::setStandardColor()} now need a \l{QColor} value as their second parameter instead of \c{QRgb}. \endlist \section1 Changes to Qt WebKit \list \li The WebKit module in Qt is now split in two modules, \c{webkit} and \c{webkitwidgets}, in order to allow the dependency of the \c{widgets} module to be optional. The benefits will only be available once the QQuickWebView API is made public through C++ in a future version. The \c{webkitwidgets} module adds the \c{webkit} module automatically to the project, so in your application's project file, \c{QT += webkit} should now be modified to: \code QT += webkitwidgets \endcode \li The same applies to the module include, \c{#include } should be modified to: \code #include \endcode \li A consequence of the module split is that classes of the \l{Qt WebKit} API aren't all in the new module, so for a better compatibility of your application with both Qt4 and Qt5, #include , for example, should be included directly as: \code #include \endcode The include path will take care of selecting the right module. \li The qwebkitversion.h header has been renamed to q\b{t}webkitversion.h to match other Qt modules, and part of its contents has been moved to qwebkitglobal.h. \c{#include } should be replaced with two includes: \code #include #include \endcode \endlist \section1 Changes to Qt Print Support \list \li The \c{QPageSetupDialog::PageSetupDialogOption} enum and the corresponding set and get functions, \c{QPageSetupDialog::options()} and \c{QPageSetupDialog::setOptions()} are removed. \li Support for printing PostScript files has been removed. \li The \c QAbstractPageSetupDialog class is removed. Use \l QPrintDialog instead. \li The \l{QPrintEngine::PrintEnginePropertyKey} enum value \c PPK_SuppressSystemPrintStatus is removed. \li \l{QPrinter} no longer allows you to set an invalid printer name. \endlist \section1 Changes to Qt Network \list \li The \c{QSsl::TlsV1} enum value is renamed as \l{QSsl::TlsV1_0}. \li The \c QHttp, \c QHttpHeader, \c QHttpResponseHeader, and \c QHttpRequestHeader classes are removed. Use \l QNetworkAccessManager instead. \li The \c QFtp and \c QUrlInfo classes are no longer exported. Use \l QNetworkAccessManager instead. Programs that require raw FTP or HTTP streams can use the \l{Qt FTP} and \l{Qt HTTP} compatibility add-on modules that provide the \c{QFtp} and \c{QHttp} classes as they existed in Qt 4. \li \l{QAbstractSocket::connectToHost()} and \l{QAbstractSocket::disconnectFromHost()} are virtual now, and \c{QAbstractSocket::connectToHostImplementation()} and \c{QAbstractSocket::disconnectFromHostImplementation()} are removed. \li \l{QTcpServer::incomingConnection()} now takes arguments of type \c{qintptr} instead of an \c{int}. \li \c{QNetworkConfiguration::bearerName()} is removed. Use the \l{QNetworkConfiguration::bearerTypeName()}{bearerTypeName()} instead. \endlist \section2 Changes to QSslCertificate \list \li \l{QSslCertificate::subjectInfo()} and \l{QSslCertificate::issuerInfo()} now return QStringList instead of a QString. This change makes searching the required information a lot easier than scanning a long string. \li \l{QSslCertificate::isValid()} is deprecated. Use \l{QSslCertificate::isBlacklisted()} instead to avoid binary breaks in the future. \li \l{QSslCertificate::alternateSubjectNames()} is deprecated. Use \l{QSslCertificate::subjectAlternativeNames()} instead. \endlist \section1 Changes to Qt SQL \list \li \l{QSqlQueryModel::indexInQuery()} is virtual now. \li \l{QSqlQueryModel::setQuery()} emits fewer signals. The \c{modelAboutToBeReset()} and \c{modelReset()} signals are sufficient to inform views that they must re-interrogate the model. \li \l{QSqlDriver::subscribeToNotification()}, \l{QSqlDriver::unsubscribeFromNotification()}, \l{QSqlDriver::subscribedToNotifications()}, \l{QSqlDriver::isIdentifierEscaped()}, and \l{QSqlDriver::stripDelimiters()} are virtual now. The corresponding \c xxxImplementation functions are also removed as the subclasses of \l{QSqlDriver} can re-implement those directly. \li \l{QSqlError} now handles alphanumeric error codes that are used by QPSQL. The numeric codes are deprecated. \endlist \section1 Changes to Qt Test \list \li The plain-text, XML and lightxml test output formats are updated to include test result for every row of test data in data-driven tests. In Qt4, only fails and skips were included for individual data rows without the passes information. This limitation prevented accurate test run and pass rates calculation. \li The \c{QTRY_VERIFY} and \c{QTRY_COMPARE} macros are now part of \c{QTestLib}. These macros were part of \c{tests/shared/util.h} earlier, but now they are part of the header. In addition, \c{QTRY_VERIFY_WITH_TIMEOUT} and \c{QTRY_COMPARE_WITH_TIMEOUT} are provided to specify custom timeout values. \li The \c{QTEST_NOOP_MAIN} macro is removed. If a test appears to be inapplicable for a particular build at compile-time, it should be omitted either using the .pro file logic or call \c{QSKIP} in the \c{initTestCase()} method to skip the entire test. If you're using the later approach, report a meaningful explanation in the test log. \li The \c{DEPENDS_ON} macro is removed as it misled some users to believe that they could make test functions depend on each other or impose an execution order on test functions. \li \c{QTest::qt_snprintf()} is removed. This was an internal test library function that was exposed in the public API due to its use in a public macro. Any calls to this function must be replaced with \l{QByteArray::qsnprintf()}. \li c{QTest::pixmapsAreEqual()} is removed. Comparison of \l{QPixmap} objects must be done using the \c{QCOMPARE} macro, which provides more informative output in the event of a failure. \li The \c{"mode"} parameter in \c{QSKIP} macro is removed. This parameter caused problems in test metrics calculation because of the \c{SkipAll} mode, which hid information about the skipped test data. Calling \c{QSKIP} in a test function now behaves like \c{SkipSingle}, which is skipping a non-data-driven test function or skipping only the current data row of a data-driven test function. Every skipped data row is now reported in the test log. \li \c{qCompare()} has been replaced by overloading. Code such as \c {qCompare(l, r)} no longer uses the QString-specific implementation and may fail to compile. We recommend that you replace specialization with overloading. Also, rather than pass explicit template arguments to \c qCompare, let the overload resolution pick the correct one, and cast arguments in case of ambiguous overloads (for example, \c {qCompare(QString(l), r)}). The resulting code will continue to work against older QtTestlib versions. \li \c QTest::qWaitForWindowShown() is replaced with \l{QTest::qWaitForWindowExposed()}. \endlist \section1 Changes to Qt OpenGL Apart from the \l QGLWidget class, the \l{Qt OpenGL} module should not be used for new code. Instead, use the corresponding \e OpenGL classes in \l{Qt GUI}. \list \li \l QGLPixelBuffer is deprecated and implemented by using a hidden \l QGLWidget and a \l QOpenGLFramebufferObject. For offscreen rendering to a texture, switch to using \l QOpenGLFramebufferObject directly to improve performance. \li The default major version of \l QGLFormat is changed to 2 to align it with \l QSurfaceFormat. Applications that want to use a different version, should explicitly request it using \l{QGLFormat::setVersion()}. \li \c{QGLContext::generateFontDisplayLists()} and \c{QGLWidget::fontDisplayListBase()} are removed. \li The \c listBase parameter is removed from \l{QGLWidget::renderText()} functions. \li To ensure support on more platforms, stricter requirements have been introduced for doing threaded \c OpenGL. First, you must call \l{QGLWidget::makeCurrent()} at least once per each \l{QGLWidget::swapBuffers()} call, so that the platform has a chance to synchronize resizing the \c OpenGL surface. Second, before calling \l{QGLWidget::makeCurrent()} or \l{QGLWidget::swapBuffers()} in a separate thread, you must call \l{QGLContext::moveToThread()} to explicitly let Qt know in which thread a \l QGLContext is currently being used. You also need to make sure that the context is not current in the current thread before moving it to a different thread. \endlist \section1 Changes to Qt Global \list \li \c{qMacVersion()} is removed. Use \l{QSysInfo::macVersion()} or \l{QSysInfo::MacintoshVersion} instead. \li \c{Qt::escape()} is deprecated. Use \l{QString::toHtmlEscaped()} instead. \li \c{qIsDetached<>} is removed, becauses it is irrelevant for multi-threaded applications. There is no replacement for this function. \endlist \section1 Changes to Tools \list \li The \c {qttest_p4.prf} file is removed. Use \c{CONFIG+=testcase} and other flags instead. \li The \c{-dwarf2} configure argument is removed. DWARF2 is always used on OS X now. \li Configure no longer calls \c{qmake -recursive} by default, because the subsequent build invokes qmake as needed. Use \c{-fully-process} to restore the old behavior. \li The \l lupdate \c CODECFORTR variable is deprecated, because source code written with Qt 5 is expected to use UTF-8 encoding. \endlist \section1 Related Topics \list \li \l{New Classes and Functions in Qt 5.4} \li \l{New Classes and Functions in Qt 5.3} \li \l{New Classes and Functions in Qt 5.2} \li \l{New Classes and Functions in Qt 5.1} \endlist */