1 Some of the changes listed in this file include issue tracking numbers
2 corresponding to tasks in the Qt Bug Tracker:
4 http://bugreports.qt-project.org/
6 Each of these identifiers can be entered in the bug tracker to obtain more
7 information about a particular change.
10 ****************************************************************************
11 * Source incompatible changes *
12 ****************************************************************************
16 * The signatures of the connectNotify() and disconnectNotify() functions
17 have changed. The functions now get passed a QMetaMethod that identifies
18 the signal, rather than a const char *.
20 - QSslCertificate::subjectInfo() and QSslCertificate::issuerInfo() now
21 return a QStringList instead of a QString
23 - QSslCertificate::isValid() has been deprecated. Originally it only checked
24 the certificate dates, but later checking for blacklisting was added. Now
25 there's a more specific QSslCertificate::isBlacklisted() method.
27 - Unite clipping support has been removed from QPainter. The alternative is
28 to unite QRegion's and using the result on QPainter.
30 - QLibrary::resolve() now returns a function pointer instead of a void
33 - QSslCertificate::alternateSubjectNames() is deprecated (but can be enabled
34 via QT_DISABLE_DEPRECATED_BEFORE), use
35 QSslCertificate::subjectAlternativeNames() instead.
37 - QLibraryInfo::buildKey() has been removed. Likewise, the QT_BUILD_KEY
38 preprocessor #define has also been removed. The build-key is obsolete
39 and is no longer necessary.
41 - QCoreApplication::translate() will no longer return the source text when
42 the translation is empty. Use lrelease -removeidentical for optimization.
44 - QString and QByteArray constructors that take a size argument will now treat
45 negative sizes to indicate nul-terminated strings (a nul-terminated array of
46 QChar, in the case of QString). In Qt 4, negative sizes were ignored and
47 result in empty QString and QByteArray, respectively. The size argument to
48 those constructors now has a default value of -1, thus replacing the separate
49 constructors that did the same.
51 - Qt::escape() is deprecated (but can be enabled via
52 QT_DISABLE_DEPRECATED_BEFORE), use QString::toHtmlEscaped() instead.
54 - QBool is gone. QString::contains, QByteArray::contains, and QList::contains
55 used to return an internal QBool class so that the Qt3 code
56 "if (a.contains() == 2)" wouldn't compile anymore. Such code cannot exist
57 in Qt4, so these methods return a bool now. If your code used the undocumented
58 QBool, simply replace it with bool.
60 - qIsDetached<> has been removed without replacement.
63 * QMetaType::construct() has been renamed to QMetaType::create().
64 * QMetaType::unregisterType() has been removed.
67 * QMetaMethod::signature() has been renamed to QMetaMethod::methodSignature(),
68 and the return type has been changed to QByteArray. This was done to be able
69 to generate the signature string on demand, rather than always storing it in
71 * QMetaMethod::typeName() no longer returns an empty string when the return
72 type is void; it returns "void". The recommended way of checking whether a
73 method returns void is to compare the return value of QMetaMethod::returnType()
77 * Inconsistent constructor taking Qt::GlobalColor and producing QVariant(QColor)
78 instance was removed. Code constructing such variants can be migrated by
79 explicitly calling QColor constructor. For example from "QVariant(Qt::red)"
80 to "QVariant(QColor(Qt::red))"
83 * The plain-text, xml and lightxml test output formats have been changed to
84 show a test result for every row of test data in data-driven tests. In
85 Qt4, only fails and skips were shown for individual data rows and passes
86 were not shown for individual data rows, preventing accurate calculation
87 of test run rates and pass rates.
88 * The QTRY_VERIFY and QTRY_COMPARE macros have been moved into QTestLib.
89 These macros formerly lived in tests/shared/util.h but are now provided
90 by including the <QtTest/QtTest> header. In addition,
91 QTRY_VERIFY_WITH_TIMEOUT and QTRY_COMPARE_WITH_TIMEOUT are provided,
92 allowing for specifying custom timeout values.
93 * The QTEST_NOOP_MAIN macro has been removed from the API. If a test is
94 known at compile-time to be inapplicable for a particular build it should
95 be omitted via .pro file logic, or the test should call QSKIP in the
96 initTestCase() method to skip the entire test and report a meaningful
97 explanation in the test log.
98 * The DEPENDS_ON macro has been removed from the API. This macro did nothing
99 and misled some users to believe that they could make test functions depend
100 on each other or impose an execution order on test functions.
101 * The QTest::qt_snprintf function has been removed from the API. This was an
102 internal testlib function that was exposed in the public API due to its use
103 in a public macro. Any calls to this function should be replaced by a call
104 to qsnprintf(), which comes from the <QtCore/QByteArray> header.
105 * The QTest::pixmapsAreEqual() function has been removed from the API.
106 Comparison of QPixmap objects should be done using QCOMPARE, which provides
107 more informative output in the event of a failure.
108 * The QSKIP macro no longer has the "mode" parameter, which caused problems
109 for calculating test metrics, as the SkipAll mode hid information about
110 what test data was skipped. Calling QSKIP in a test function now behaves
111 like SkipSingle -- skipping a non-data-driven test function or skipping
112 only the current data row of a data-driven test function. Every skipped
113 data row is now reported in the test log.
115 - The QSsl::TlsV1 enum value was renamed to QSsl::TlsV1_0 .
118 * Internal QAccessible::State enum value HasInvokeExtension removed
119 - QAccessibleInterface:
120 * The "child" integer parameters have been removed. This moves the api
121 to be closer to IAccessible2.
122 This means several functions lose their integer parameter:
123 text(Text t, int child) -> text(Text t), rect(int child) -> rect()
124 setText(Text t, int child, const QString &text) -> setText(Text t, const QString &text)
125 role(int child) -> role(), state(int child) -> state()
126 * parent() and child() was added in order to do hierarchical navigation.
127 * relations() was added as a replacement to relationTo()
128 * As a consequence of the above two points, navigate() was removed.
129 * Accessible-Action related functions have been removed. QAccessibleInterface
130 subclasses are expected to implement the QAccessibleActionInterface instead.
131 These functions have been removed:
132 QAccessibleInterface::userActionCount, QAccessibleInterface::actionText,
133 QAccessibleInterface::doAction
134 - QAccessibleEvent also loses the child parameter.
135 QAccessibleEvent(Type type, int child) -> QAccessibleEvent(Type type)
136 QAccessibleEvent::child() removed.
137 - QAccessibleActionInterface:
138 * Refactored to be based on action names. All functions have been changed from using
139 int parameters to strings.
141 - QSound has been moved from QtGui to QtMultimedia
143 - QTabletEvent::QTabletEvent does not take a hiResGlobalPos argument anymore,
144 as all coordinates are floating point based now.
148 * The DeviceType enum and deviceType() have been deprecated due to
149 the introduction of QTouchDevice.
151 * The signature of the constructor has changed. It now takes a
152 QTouchDevice pointer instead of just a DeviceType value.
154 * TouchPointState no longer includes TouchPointStateMask and
155 TouchPointPrimary. QTouchEvent::TouchPoint::isPrimary() has
158 * QWidget *widget() has been removed and is replaced by QObject
159 *target() in order to avoid QWidget dependencies.
161 * QEvent::TouchCancel has been introduced. On systems where it makes
162 sense this event type can be used to differentiate between a
163 regular TouchEnd and abrupt touch sequence cancellations caused by
164 the compositor, for example when a system gesture gets recognized.
168 * Q_DECLARE_METATYPE(Foo*) now requires that Foo is fully defined. In
169 cases where a forward declared type should be used as a metatype,
170 Q_DECLARE_OPAQUE_POINTER(Foo*) can be used to allow that.
171 * Similarly, Q_DECLARE_METATYPE(QSharedPointer<Foo>), and
172 Q_DECLARE_METATYPE(QWeakPointer<Foo>) require Foo to be fully defined. Again
173 though, Q_DECLARE_OPAQUE_POINTER(Foo*) can be used to allow that.
177 * The signature of the createEditor and valuePropertyName methods
178 have been changed to take arguments of type int instead of QVariant::Type.
180 - QWindowSystemInterface:
182 * The signature of all handleTouchEvent() variants have changed,
183 taking a QTouchDevice* instead of just a DeviceType value.
184 Platform or generic plug-ins have to create and register at least
185 one QTouchDevice before sending the first touch event.
187 * The event type parameter is removed from handleTouchEvent().
189 - The previously exported function qt_translateRawTouchEvent() has been removed.
190 Use QWindowSystemInterface::handleTouchEvent() instead.
192 - QAbstractEventDispatcher
194 * The signature for the pure-virtual registerTimer() has changed. Subclasses
195 of QAbstractEventDispatcher will need to be updated to reimplement the new
196 pure-virtual 'virtual void registerTimer(int timerId, int interval,
197 Qt::TimerType timerType, QObject *object) = 0;'
199 * QAbstractEventDispatcher::TimerInfo is no longer a QPair<int, int>. It is
200 now a struct with 3 members: struct TimerInfo { int timerId; int interval;
201 Qt::TimerType timerType; }; Reimplementations of
202 QAbstractEventDispatcher::registeredTimers() will need to be updated to pass
203 3 arguments to the TimerInfo constructor (instead of 2).
207 * Removed implicit conversion operator QUuid::operator QString(), instead
208 QUuid::toString() function should be used.
210 - The QHttp, QHttpHeader, QHttpResponseHeader and QHttpRequestHeader classes have
211 been removed, QNetworkAccessManager should be used instead.
213 - The QFtp and QUrlInfo classes are no longer exported, QNetworkAccessManager should be used
214 instead. These classes are available in a separate module, qtftp.
218 * On Windows, QProcess::ForwardedChannels will not forward the output of GUI
219 applications anymore, if they do not create a console.
221 - QAbstractSocket's connectToHost() and disconnectFromHost() are now virtual and
222 connectToHostImplementation() and disconnectFromHostImplementation() don't exist.
224 - QTcpServer::incomingConnection() now takes a qintptr instead of an int.
226 - QNetworkConfiguration::bearerName() removed, and bearerTypeName() should be used.
228 - QDir::convertSeparators() (deprecated since Qt 4.2) has been removed. Use
229 QDir::toNativeSeparators() instead.
231 - QIconEngineV2 was merged into QIconEngine
232 You might need to adjust your code if it used a QIconEngine.
235 * Projects which explicitly set an empty TARGET are considered broken now.
236 * The makespec and .qmake.cache do not see build pass specific variables any more.
237 * load()/include() with a target namespace and infile()/$$fromfile() now start with
238 an entirely pristine context.
239 * Configure's -sysroot and -hostprefix are now handled slightly differently.
240 The QT_INSTALL_... properties are now automatically prefixed with the sysroot;
241 the raw values are available as QT_INSTALL_.../raw and the sysroot as QT_SYSROOT.
242 The new QT_HOST_... properties can be used to refer to the Qt host tools.
243 * Several functions and built-in variables were modified to return normalized paths.
244 * The -(no-)exception flags in configure have been removed. Qt modules are now compiled
245 without exceptions by default, as they do not use them and can neither handle them
246 properly. Qt Core still has exceptions enabled to correctly throw bad_alloc exceptions
248 Whether code should be compiled with exception support enabled or disabled can be
249 controlled by a CONFIG += exceptions/exceptions_off setting in the .pro file.
251 - QTextCodecPlugin has been removed since it is no longer used. All text codecs
252 are now built into QtCore.
254 - QDir::NoDotAndDotDot is QDir::NoDot|QDir::NoDotDot therefore there is no need
255 to use or check both.
257 - QFSFileEngine, QAbstractFileEngine, QAbstractFileEngineIterator and
258 QAbstractFileEngineHandler were removed from public API and are no longer
259 exported. They may temporarily live as private implementation details, but
260 they may be altogether dropped or otherwise changed at will in the future.
263 * toShort(), toUShort(), toInt(), toUInt(), toLongLong() and toULongLong() no
264 longer take a parameter for base, they will only perform localised base 10
265 conversions. For converting other bases use the QString methods instead.
267 - QSystemLocale has been removed from the public API.
269 - QSqlQueryModel::indexInQuery() is now virtual. See note below under QtSql.
271 - QSqlDriver::subscribeToNotification, unsubscribeFromNotification,
272 subscribedToNotifications, isIdentifierEscaped, and stripDelimiters
273 are now virtual. See note below under QtSql.
275 - qMacVersion() has been removed. Use QSysInfo::macVersion() or
276 QSysInfo::MacintoshVersion instead.
278 - QColorDialog::customColor() now returns a QColor value instead of QRgb.
279 QColorDialog::setCustomColor() and QColorDialog::setStandardColor() now
280 take a QColor value for their second parameter instead of QRgb.
282 - QPageSetupDialog has had the PageSetupDialogOption enum and the api to
283 set and get the enum removed as none of the Options are used any more.
285 ****************************************************************************
287 ****************************************************************************
292 - The directory structure of the qtbase unit-tests has been reworked to
293 more closely match the directory structure of the code under test.
294 Integration tests have been moved to tests/auto/integrationtests.
296 - Qt is compiled with C++11 support enabled by default, provided the compiler
297 supports C++11. Qmake based projects can enable C++11 support explicitly
298 using 'CONFIG+=c++11' in their .pro files. To enable it conditionally, use
299 'contains(QT_CONFIG,c++11):CONFIG+=c++11'. This will enable C++11 support
300 only if Qt was built with C++11 support.
302 Third party components
303 ----------------------
305 - SQLITE_ENABLE_FTS3,SQLITE_ENABLE_FTS3_PARENTHESIS and SQLITE_ENABLE_RTREE
306 flags are now enabled by default on all platforms, for the sqlite3 copy under
307 the 3rdparty directory.
310 ****************************************************************************
312 ****************************************************************************
316 * drop a bogus QChar::NoCategory enum value; the proper QChar::Other_NotAssigned
317 value is returned for an unassigned codepoints now.
319 * layoutAboutToBeChanged is no longer emitted by QAbstractItemModel::beginMoveRows.
320 layoutChanged is no longer emitted by QAbstractItemModel::endMoveRows. Proxy models
321 should now also connect to (and disconnect from) the rowsAboutToBeMoved and
324 * The default value of the property QSortFilterProxyModel::dynamicSortFilter was
325 changed from false to true.
327 * The signature of the virtual QAbstractItemView::dataChanged method has changed to
328 include the roles which have changed. The signature is consistent with the dataChanged
331 * QFileSystemWatcher is now able to return failure in case of errors whilst
332 altering the watchlist in both the singular and QStringList overloads of
333 addPath and removePath.
335 * QString::mid, QString::midRef and QByteArray::mid, if the position passed
336 is equal to the length (that is, right after the last character/byte),
337 now return an empty QString, QStringRef or QByteArray respectively.
338 in Qt 4 they returned a null QString or a null QStringRef.
340 * QString methods toLongLong(), toULongLong(), toLong(), toULong(), toInt(),
341 toUInt(), toShort(), toUShort(), toDouble(), and toFloat() no longer use the
342 default or system locale, they will always use the C locale. This is to
343 guarantee consistent default conversion of strings. For locale-aware conversions
344 use the equivalent QLocale methods.
346 * QDate, QTime, and QDateTime have undergone important behavioural changes:
347 * QDate only implements the Gregorian calendar, the switch to the Julian
348 calendar before 1582 has been removed. This means all QDate methods will
349 return different results for dates prior to 15 October 1582, and there is
350 no longer a gap between 4 October 1582 and 15 October 1582.
351 * QDate::setYMD() is deprecated, use QDate::setDate() instead
352 * Most methods now apply strict validity checks and will return appropriate
353 and consistent values when invalid. For example, QDate::year() will return
354 0 and QDate::shortMonthName() will return QString().
355 * Adding days to a null QDate or seconds to a null QTime will no longer return
357 * QDate stores the Julian Day as a qint64 extending date support across a
358 more interesting range, see the class documentation for details.
359 * Conversion to YMD form dates is only accurate between to 4800 BCE to
361 * The QDate::addDays() and QDateTime::addDays() methods now take a qint64
362 * The QDate::daysTo() and QDateTime::daysTo() methods now return a qint64
364 * QTextCodec::codecForCStrings() and QTextCodec::setCodecForCStrings() have both
365 been removed. This was removed due to issues with breaking other code from
366 libraries, creating uncertainty/bugs in using QString easily, and (to a lesser
367 extent) performance issues.
369 * QTextCodec::codecForTr() and QTextCodec::setCodecForTr() have been removed.
370 QObject::trUtf8 and QCoreApplication::Encoding enum are now obsolete. Qt assumes
371 that the source code is encoded in UTF-8.
373 * QFile::setEncodingFunction and QFile::setDecodingFunction are obsolete and do
374 nothing in Qt 5. The QFile::encodeName and QFile::decodeName functions are now
375 hardcoded to operate on QString::fromLocal8Bit and QString::toLocal8Bit
376 only. Therefore, it's still possible to obtain the old behaviour by calling
377 QTextCodec::setCodecForLocale. However, that is not recommended: new code
378 should not make assumptions about the filesystem encoding and older code should
379 have those assumptions removed.
381 * QIntValidator and QDoubleValidator no longer fall back to using the C locale if
382 the requested locale fails to validate the input.
384 * A new set of classes for doing pattern matching with Perl-compatible regular
385 expressions has been added: QRegularExpression, QRegularExpressionMatch and
386 QRegularExpressionMatchIterator. They aim to replace QRegExp with a more
387 powerful and flexible regular expression engine.
389 * QEvent::AccessibilityPrepare, AccessibilityHelp and AccessibilityDescription removed:
390 * The enum values simply didn't make sense in the first place and should simply be dropped.
392 * [QTBUG-23529] QHash is now more resilient to a family of denial of service
393 attacks exploiting algorithmic complexity, by supporting two-arguments overloads
394 of the qHash() hashing function.
398 * Accessibility has been refactored. The hierachy of accessible objects is implemented via
399 proper parent/child functions instead of using navigate which has been deprecated for this purpose.
400 Table and cell interfaces have been added to qaccessible2.h
402 * Touch events and points have been extended to hold additional
403 information like capability flags, point-specific flags, velocity,
406 * A new set of enabler classes have been added, most importantly QWindow, QScreen,
407 QSurfaceFormat, and QOpenGLContext.
409 * Most of the useful QtOpenGL classes have been polished and moved into
410 QtGui. See QOpenGLFramebufferObject, QOpenGLShaderProgram,
411 QOpenGLFunctions, etc.
413 * QOpenGLPaintDevice has been added to be able to use QPainter to render into
414 the currently bound context.
418 * QInputContext removed as well as related getters and setters on QWidget and QApplication.
419 Input contexts are now platform specific.
421 * QInputDialog::getInteger() has been obsoleted. Use QInputDialog::getInt() instead.
423 * In Qt 4, many QStyleOption subclasses were introduced in order to keep
424 binary compatibility -- QStyleOption was designed to be extended this way,
425 in fact it embeds a version number. In Qt 5 the various QStyleOption*V{2,3,4}
426 classes have been removed, and their members merged into the respective
427 base classes. Those classes were left as typedefs to keep existing code
428 working. Still, some minor adjustements could be necessary, especially in code
429 that uses QStyleOption directly and does not initialize all the members using
430 the proper Qt API: due to the version bump, QStyle will try to use the additional
431 QStyleOption members, which are left default-initialized.
433 * QHeaderView - The following functions have been obsoleted.
435 * void setMovable(bool movable) - use void setSectionsMovable(bool movable) instead.
437 * bool isMovable() const - use bool sectionsMovable() const instead.
439 * void setClickable(bool clickable) - use void setSectionsClickable(bool clickable) instead.
441 * bool isClickable() const - use bool sectionsClickable() instead.
443 * void setResizeMode(int logicalindex, ResizeMode mode) -
444 use setSectionResizeMode(logicalindex, mode) instead.
446 * ResizeMode resizeMode(int logicalindex) const -
447 use sectionResizeMode(int logicalindex) instead.
449 * QDateEdit and QTimeEdit have re-gained a USER property. These were originally removed
450 before Qt 4.7.0, and are re-added for 5.0. This means that the userProperty for
451 those classes are now QDate and QTime respectively, not QDateTime as they have been
452 for the 4.7 and 4.8 releases.
456 * QHostAddress::isLoopback() API added. Returns true if the address is
457 one of the IP loopback addresses.
459 * QSslCertificate::serialNumber() now always returns the serial number in
462 * The openssl network backend now reads the ssl configuration file allowing
463 the use of openssl engines.
467 * QtDBus now generates property annotations for the Qt type names
468 in the org.qtproject.QtDBus namespace. When parsing such annotations
469 both the old and new namespaces are accepted.
471 * QtDBus error codes have been updated to be on the org.qtproject.QtDBus.Error
477 * Most of the classes in this module (with the notable exception of QGLWidget)
478 now have equivalents in QtGui, along with the naming change QGL -> QOpenGL.
479 The classes in QtOpenGL that have equivalents in QtGui can now be considered
488 * [QTBUG-20615] Autotests can now log test output to multiple destinations
489 and log formats simultaneously.
493 QSqlQueryModel/QSqlTableModel/QSqlRelationalTableModel
495 * The dataChanged() signal is now emitted for changes made to an inserted
496 record that has not yet been committed. Previously, dataChanged() was
497 suppressed in this case for OnRowChange and OnFieldChange. This was probably
498 an attempt to avoid trouble if setData() was called while handling
499 primeInsert(). By emitting dataChanged(), we ensure that all views are aware
502 * While handling primeInsert() signal, the record must be manipulated using
503 the provided reference. Do not attempt to manipulate the records using the
504 model methods setData() or setRecord().
506 * removeRows() no longer emits extra beforeDelete signal for out of range row.
508 * removeRows() now requires the whole range of targetted rows to be valid
509 before doing anything. Previously, it would remove what it could and
510 ignore the rest of the range.
512 * removeRows(), for OnFieldChange and OnRowChange, allows only 1 row to be
513 removed and only if there are no other changed rows.
515 * setRecord() and insertRecord()
516 -Only use fields where generated flag is set to true. This is
517 is consistent with the meaning of the flag.
518 -Require all fields to map correctly. Previously fields that didn't
519 map were simply ignored.
520 -For OnManualSubmit, insertRecord() no longer leaves behind an empty
521 row if setRecord() fails.
522 -setRecord() now automatically submits for OnRowChange.
524 * QSqlQueryModel::indexInQuery() is now virtual. See
525 QSqlTableModel::indexInQuery() as example of how to implement in a
528 * QSqlQueryMode::setQuery() emits fewer signals. The modelAboutToBeReset()
529 and modelReset() signals suffice to inform views that they must reinterrogate
532 * QSqlTableModel::selectRow(): This is a new method that refreshes a single
533 row in the model from the database.
535 * QSqlTableModel edit strategies OnFieldChange/OnRowChange QTBUG-2875
536 Previously, after changes were submitted in these edit strategies, select()
537 was called which removed and inserted all rows. This ruined navigation
538 in QTableView. Now, with these edit strategies, there is no implicit select()
539 done after committing. This includes deleted rows which remain in
540 the model as blank rows until the application calls select(). Instead,
541 selectRow() is called to refresh only the affected row.
543 * QSqlTableModel::isDirty(): New overloaded method to check whether model
544 has any changes to submit. QTBUG-3108
546 * QSqlTableModel::setData() and setRecord() no longer revert pending changes
547 that fail upon resubmitting for edit strategies OnFieldChange and OnRowChange.
548 Instead, pending (failed) changes cause new changes inappropriate to the
549 edit strategy to be refused. The application should resolve or revert pending
550 changes. insertRows() and insertRecord() also respect the edit strategy.
552 * QSqlTableModel::setData() and setRecord() in OnRowChange no longer have the
553 side effect of submitting the cached row when invoked on a different row.
555 * QSqlDriver::subscribeToNotification, unsubscribeFromNotification,
556 subscribedToNotifications, isIdentifierEscaped, and stripDelimiters
557 are now virtual. Their xxxImplemenation counterparts have been removed
558 now that QSqlDriver subclasses can reimplement these directly.
560 ****************************************************************************
562 ****************************************************************************
566 * QVariant::Bool type now mapped to integers 0/1 in SQL instead of strings
567 'true' and 'false'. Sqlite does not have a boolean column type and it is
568 customary to use integer. QTBUG-23895
570 ****************************************************************************
571 * Platform Specific Changes *
572 ****************************************************************************
580 * Accessibility framework uses IAccessible2
581 * ANGLE can be used to provide Open GL ES 2.0 (see http://code.google.com/p/angleproject/)
587 Qt for Embedded Linux
588 ---------------------
595 ****************************************************************************
596 * Compiler Specific Changes *
597 ****************************************************************************
600 ****************************************************************************
602 ****************************************************************************
606 * Remove qttest_p4.prf file. From now on we should explicitly enable the
607 things from it which we want. Autotest .pro files should stop using
608 'load(qttest_p4)' and start using 'CONFIG+=testcase' instead.
613 * [QTBUG-8926] [QTBUG-20440] Properties of type QStringList now have
614 translation attributes which apply to all items.
615 They are by default translatable.
624 * [QTBUG-20785] The moc now has a -b<file> option to #include an additional
625 file at the beginning of the generated file.
636 * QMAKE_MOC_OPTIONS variable is now available for passing additional parameters
642 * The Mac OS X -dwarf2 configure argument has been removed. DWARF2 is always
643 used on Mac OS X now.
648 ****************************************************************************
650 ****************************************************************************
651 - The text codecs that were previously plugins are now built into QtCore.
653 ****************************************************************************
654 * Important Behavior Changes *
655 ****************************************************************************
659 * The implementation of QPointer has been changed to use QWeakPointer. The
660 old guard mechanism has been removed. This causes a slight change
661 in behavior when using QPointer:
663 * When using QPointer on a QWidget (or a subclass of QWidget), previously
664 the QPointer would be cleared by the QWidget destructor. Now, the QPointer
665 is cleared by the QObject destructor (since this is when QWeakPointers are
666 cleared). Any QPointers tracking a widget will NOT be cleared before the
667 QWidget destructor destroys the children for the widget being tracked.
671 * QUrl has been changed to operate only on percent-encoded
672 forms. Fully-decoded forms, where the percent character stands for itself,
673 are no longer possible. For that reason, the getters and setters with
674 "encoded" in the name are deprecated, except for QUrl::toEncoded() and
677 QUrl now operates in a mode where it decodes as much as it can of the
678 percent-encoding sequences. In addition, the setter methods possess a mode
679 in which a '%' character not part of a percent-encoding sequence will cause
680 the parser to correct the input. Therefore, most software will not require
681 changes to adapt, since the getter methods will continue returning the
682 components in their most-decoded form as they did before and the setter
683 methods will accept input as they did before..
685 The most notable difference is when dealing with
686 QUrl::toString(). Previously, this function would return percent characters
687 in the URL by themselves. Now, it will return "%25", like
692 * Definition of QVariant::UserType changed. Currently it is the same as
693 QMetaType::User, which means that it points to the first registered custom
694 type, instead of a nonexistent type.
698 * Interpretation of QMetaType::Void was changed. Before, in some cases
699 it was returned as an invalid type id, but sometimes it was used as a valid
700 type (C++ "void"). In Qt5, new QMetaType::UnknownType was introduced to
701 distinguish between these two. QMetaType::UnknownType is an invalid type id
702 signaling that a type is unknown to QMetaType, and QMetaType::Void
703 is a valid type id of C++ void type. The difference will be visible for
704 example in call to QMetaType::typeName(), this function will return null for
705 QMetaType::UnknownType and a pointer to "void" string for
707 Please, notice that QMetaType::UnknownType has value 0, which previously was
708 reserved for QMetaType::Void.
713 * The static function QMessageBox::question has changed the default argument
714 for buttons. Before the default was to have an Ok button. That is changed
715 to having a yes and a no button.