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 The build-key is obsolete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.
174 * The signature of the createEditor and valuePropertyName methods
175 have been changed to take arguments of type int instead of QVariant::Type.
177 - QWindowSystemInterface:
179 * The signature of all handleTouchEvent() variants have changed,
180 taking a QTouchDevice* instead of just a DeviceType value.
181 Platform or generic plug-ins have to create and register at least
182 one QTouchDevice before sending the first touch event.
184 * The event type parameter is removed from handleTouchEvent().
186 - The previously exported function qt_translateRawTouchEvent() has been removed.
187 Use QWindowSystemInterface::handleTouchEvent() instead.
189 - QAbstractEventDispatcher
191 * The signature for the pure-virtual registerTimer() has changed. Subclasses
192 of QAbstractEventDispatcher will need to be updated to reimplement the new
193 pure-virtual 'virtual void registerTimer(int timerId, int interval,
194 Qt::TimerType timerType, QObject *object) = 0;'
196 * QAbstractEventDispatcher::TimerInfo is no longer a QPair<int, int>. It is
197 now a struct with 3 members: struct TimerInfo { int timerId; int interval;
198 Qt::TimerType timerType; }; Reimplementations of
199 QAbstractEventDispatcher::registeredTimers() will need to be updated to pass
200 3 arguments to the TimerInfo constructor (instead of 2).
204 * Removed implicit conversion operator QUuid::operator QString(), instead
205 QUuid::toString() function should be used.
207 - The QHttp, QHttpHeader, QHttpResponseHeader and QHttpRequestHeader classes have
208 been removed, QNetworkAccessManager should be used instead.
210 - The QFtp class is no longer exported, QNetworkAccessManager should be used
215 * On Windows, QProcess::ForwardedChannels will not forward the output of GUI
216 applications anymore, if they do not create a console.
218 - QAbstractSocket's connectToHost() and disconnectFromHost() are now virtual and
219 connectToHostImplementation() and disconnectFromHostImplementation() don't exist.
221 - QTcpServer::incomingConnection() now takes a qintptr instead of an int.
223 - QNetworkConfiguration::bearerName() removed, and bearerTypeName() should be used.
225 - QDir::convertSeparators() (deprecated since Qt 4.2) has been removed. Use
226 QDir::toNativeSeparators() instead.
228 - QIconEngineV2 was merged into QIconEngine
229 You might need to adjust your code if it used a QIconEngine.
232 * Projects which explicitly set an empty TARGET are considered broken now.
233 * The makespec and .qmake.cache do not see build pass specific variables any more.
234 * load()/include() with a target namespace and infile()/$$fromfile() now start with
235 an entirely pristine context.
236 * Configure's -sysroot and -hostprefix are now handled slightly differently.
237 The QT_INSTALL_... properties are now automatically prefixed with the sysroot;
238 the raw values are available as QT_INSTALL_.../raw and the sysroot as QT_SYSROOT.
239 The new QT_HOST_... properties can be used to refer to the Qt host tools.
240 * Several functions and built-in variables were modified to return normalized paths.
241 * The -(no-)exception flags in configure have been removed. Qt modules are now compiled
242 without exceptions by default, as they do not use them and can neither handle them
243 properly. Qt Core still has exceptions enabled to correctly throw bad_alloc exceptions
245 Whether code should be compiled with exception support enabled or disabled can be
246 controlled by a CONFIG += exceptions/exceptions_off setting in the .pro file.
248 - QTextCodecPlugin has been removed since it is no longer used. All text codecs
249 are now built into QtCore.
251 - QDir::NoDotAndDotDot is QDir::NoDot|QDir::NoDotDot therefore there is no need
252 to use or check both.
254 - QFSFileEngine, QAbstractFileEngine, QAbstractFileEngineIterator and
255 QAbstractFileEngineHandler were removed from public API and are no longer
256 exported. They may temporarily live as private implementation details, but
257 they may be altogether dropped or otherwise changed at will in the future.
260 * toShort(), toUShort(), toInt(), toUInt(), toLongLong() and toULongLong() no
261 longer take a parameter for base, they will only perform localised base 10
262 conversions. For converting other bases use the QString methods instead.
264 - QSystemLocale has been removed from the public API.
266 - QSqlQueryModel::indexInQuery() is now virtual. See note below under QtSql.
268 - QSqlDriver::subscribeToNotification, unsubscribeFromNotification,
269 subscribedToNotifications, isIdentifierEscaped, and stripDelimiters
270 are now virtual. See note below under QtSql.
272 - qMacVersion() has been removed. Use QSysInfo::macVersion() or
273 QSysInfo::MacintoshVersion instead.
275 - QColorDialog::customColor() now returns a QColor value instead of QRgb.
276 QColorDialog::setCustomColor() and QColorDialog::setStandardColor() now
277 take a QColor value for their second parameter instead of QRgb.
279 - QPageSetupDialog has had the PageSetupDialogOption enum and the api to
280 set and get the enum removed as none of the Options are used any more.
282 ****************************************************************************
284 ****************************************************************************
289 - The directory structure of the qtbase unit-tests has been reworked to
290 more closely match the directory structure of the code under test.
291 Integration tests have been moved to tests/auto/integrationtests.
293 - Qt is compiled with C++11 support enabled by default, provided the compiler
294 supports C++11. Qmake based projects can enable C++11 support explicitly
295 using 'CONFIG+=c++11' in their .pro files. To enable it conditionally, use
296 'contains(QT_CONFIG,c++11):CONFIG+=c++11'. This will enable C++11 support
297 only if Qt was built with C++11 support.
299 Third party components
300 ----------------------
302 - SQLITE_ENABLE_FTS3,SQLITE_ENABLE_FTS3_PARENTHESIS and SQLITE_ENABLE_RTREE
303 flags are now enabled by default on all platforms, for the sqlite3 copy under
304 the 3rdparty directory.
307 ****************************************************************************
309 ****************************************************************************
313 * drop a bogus QChar::NoCategory enum value; the proper QChar::Other_NotAssigned
314 value is returned for an unassigned codepoints now.
316 * layoutAboutToBeChanged is no longer emitted by QAbstractItemModel::beginMoveRows.
317 layoutChanged is no longer emitted by QAbstractItemModel::endMoveRows. Proxy models
318 should now also connect to (and disconnect from) the rowsAboutToBeMoved and
321 * The default value of the property QSortFilterProxyModel::dynamicSortFilter was
322 changed from false to true.
324 * The signature of the virtual QAbstractItemView::dataChanged method has changed to
325 include the roles which have changed. The signature is consistent with the dataChanged
328 * QFileSystemWatcher is now able to return failure in case of errors whilst
329 altering the watchlist in both the singular and QStringList overloads of
330 addPath and removePath.
332 * QString::mid, QString::midRef and QByteArray::mid, if the position passed
333 is equal to the length (that is, right after the last character/byte),
334 now return an empty QString, QStringRef or QByteArray respectively.
335 in Qt 4 they returned a null QString or a null QStringRef.
337 * QString methods toLongLong(), toULongLong(), toLong(), toULong(), toInt(),
338 toUInt(), toShort(), toUShort(), toDouble(), and toFloat() no longer use the
339 default or system locale, they will always use the C locale. This is to
340 guarantee consistent default conversion of strings. For locale-aware conversions
341 use the equivalent QLocale methods.
343 * QDate, QTime, and QDateTime have undergone important behavioural changes:
344 * QDate only implements the Gregorian calendar, the switch to the Julian
345 calendar before 1582 has been removed. This means all QDate methods will
346 return different results for dates prior to 15 October 1582, and there is
347 no longer a gap between 4 October 1582 and 15 October 1582.
348 * QDate::setYMD() is deprecated, use QDate::setDate() instead
349 * Most methods now apply strict validity checks and will return appropriate
350 and consistent values when invalid. For example, QDate::year() will return
351 0 and QDate::shortMonthName() will return QString().
352 * Adding days to a null QDate or seconds to a null QTime will no longer return
354 * QDate stores the Julian Day as a qint64 extending date support across a
355 more interesting range, see the class documentation for details.
356 * Conversion to YMD form dates is only accurate between to 4800 BCE to
358 * The QDate::addDays() and QDateTime::addDays() methods now take a qint64
359 * The QDate::daysTo() and QDateTime::daysTo() methods now return a qint64
361 * QTextCodec::codecForCStrings() and QTextCodec::setCodecForCStrings() have both
362 been removed. This was removed due to issues with breaking other code from
363 libraries, creating uncertainty/bugs in using QString easily, and (to a lesser
364 extent) performance issues.
366 * QTextCodec::codecForTr() and QTextCodec::setCodecForTr() have been removed.
367 QObject::trUtf8 and QCoreApplication::Encoding enum are now obsolete. Qt assumes
368 that the source code is encoded in UTF-8.
370 * QFile::setEncodingFunction and QFile::setDecodingFunction are obsolete and do
371 nothing in Qt 5. The QFile::encodeName and QFile::decodeName functions are now
372 hardcoded to operate on QString::fromLocal8Bit and QString::toLocal8Bit
373 only. Therefore, it's still possible to obtain the old behaviour by calling
374 QTextCodec::setCodecForLocale. However, that is not recommended: new code
375 should not make assumptions about the filesystem encoding and older code should
376 have those assumptions removed.
378 * QIntValidator and QDoubleValidator no longer fall back to using the C locale if
379 the requested locale fails to validate the input.
381 * A new set of classes for doing pattern matching with Perl-compatible regular
382 expressions has been added: QRegularExpression, QRegularExpressionMatch and
383 QRegularExpressionMatchIterator. They aim to replace QRegExp with a more
384 powerful and flexible regular expression engine.
386 * QEvent::AccessibilityPrepare, AccessibilityHelp and AccessibilityDescription removed:
387 * The enum values simply didn't make sense in the first place and should simply be dropped.
389 * [QTBUG-23529] QHash is now more resilient to a family of denial of service
390 attacks exploiting algorithmic complexity, by supporting two-arguments overloads
391 of the qHash() hashing function.
395 * Accessibility has been refactored. The hierachy of accessible objects is implemented via
396 proper parent/child functions instead of using navigate which has been deprecated for this purpose.
397 Table and cell interfaces have been added to qaccessible2.h
399 * Touch events and points have been extended to hold additional
400 information like capability flags, point-specific flags, velocity,
403 * A new set of enabler classes have been added, most importantly QWindow, QScreen,
404 QSurfaceFormat, and QOpenGLContext.
406 * Most of the useful QtOpenGL classes have been polished and moved into
407 QtGui. See QOpenGLFramebufferObject, QOpenGLShaderProgram,
408 QOpenGLFunctions, etc.
410 * QOpenGLPaintDevice has been added to be able to use QPainter to render into
411 the currently bound context.
415 * QInputContext removed as well as related getters and setters on QWidget and QApplication.
416 Input contexts are now platform specific.
418 * QInputDialog::getInteger() has been obsoleted. Use QInputDialog::getInt() instead.
420 * In Qt 4, many QStyleOption subclasses were introduced in order to keep
421 binary compatibility -- QStyleOption was designed to be extended this way,
422 in fact it embeds a version number. In Qt 5 the various QStyleOption*V{2,3,4}
423 classes have been removed, and their members merged into the respective
424 base classes. Those classes were left as typedefs to keep existing code
425 working. Still, some minor adjustements could be necessary, especially in code
426 that uses QStyleOption directly and does not initialize all the members using
427 the proper Qt API: due to the version bump, QStyle will try to use the additional
428 QStyleOption members, which are left default-initialized.
430 * QHeaderView - The following functions have been obsoleted.
432 * void setMovable(bool movable) - use void setSectionsMovable(bool movable) instead.
434 * bool isMovable() const - use bool sectionsMovable() const instead.
436 * void setClickable(bool clickable) - use void setSectionsClickable(bool clickable) instead.
438 * bool isClickable() const - use bool sectionsClickable() instead.
440 * void setResizeMode(int logicalindex, ResizeMode mode) -
441 use setSectionResizeMode(logicalindex, mode) instead.
443 * ResizeMode resizeMode(int logicalindex) const -
444 use sectionResizeMode(int logicalindex) instead.
446 * QDateEdit and QTimeEdit have re-gained a USER property. These were originally removed
447 before Qt 4.7.0, and are re-added for 5.0. This means that the userProperty for
448 those classes are now QDate and QTime respectively, not QDateTime as they have been
449 for the 4.7 and 4.8 releases.
453 * QHostAddress::isLoopback() API added. Returns true if the address is
454 one of the IP loopback addresses.
456 * QSslCertificate::serialNumber() now always returns the serial number in
459 * The openssl network backend now reads the ssl configuration file allowing
460 the use of openssl engines.
464 * QtDBus now generates property annotations for the Qt type names
465 in the org.qtproject.QtDBus namespace. When parsing such annotations
466 both the old and new namespaces are accepted.
468 * QtDBus error codes have been updated to be on the org.qtproject.QtDBus.Error
474 * Most of the classes in this module (with the notable exception of QGLWidget)
475 now have equivalents in QtGui, along with the naming change QGL -> QOpenGL.
476 The classes in QtOpenGL that have equivalents in QtGui can now be considered
485 * [QTBUG-20615] Autotests can now log test output to multiple destinations
486 and log formats simultaneously.
490 QSqlQueryModel/QSqlTableModel/QSqlRelationalTableModel
492 * The dataChanged() signal is now emitted for changes made to an inserted
493 record that has not yet been committed. Previously, dataChanged() was
494 suppressed in this case for OnRowChange and OnFieldChange. This was probably
495 an attempt to avoid trouble if setData() was called while handling
496 primeInsert(). By emitting dataChanged(), we ensure that all views are aware
499 * While handling primeInsert() signal, the record must be manipulated using
500 the provided reference. Do not attempt to manipulate the records using the
501 model methods setData() or setRecord().
503 * removeRows() no longer emits extra beforeDelete signal for out of range row.
505 * removeRows() now requires the whole range of targetted rows to be valid
506 before doing anything. Previously, it would remove what it could and
507 ignore the rest of the range.
509 * removeRows(), for OnFieldChange and OnRowChange, allows only 1 row to be
510 removed and only if there are no other changed rows.
512 * setRecord() and insertRecord()
513 -Only use fields where generated flag is set to true. This is
514 is consistent with the meaning of the flag.
515 -Require all fields to map correctly. Previously fields that didn't
516 map were simply ignored.
517 -For OnManualSubmit, insertRecord() no longer leaves behind an empty
518 row if setRecord() fails.
519 -setRecord() now automatically submits for OnRowChange.
521 * QSqlQueryModel::indexInQuery() is now virtual. See
522 QSqlTableModel::indexInQuery() as example of how to implement in a
525 * QSqlQueryMode::setQuery() emits fewer signals. The modelAboutToBeReset()
526 and modelReset() signals suffice to inform views that they must reinterrogate
529 * QSqlTableModel::selectRow(): This is a new method that refreshes a single
530 row in the model from the database.
532 * QSqlTableModel edit strategies OnFieldChange/OnRowChange QTBUG-2875
533 Previously, after changes were submitted in these edit strategies, select()
534 was called which removed and inserted all rows. This ruined navigation
535 in QTableView. Now, with these edit strategies, there is no implicit select()
536 done after committing. This includes deleted rows which remain in
537 the model as blank rows until the application calls select(). Instead,
538 selectRow() is called to refresh only the affected row.
540 * QSqlTableModel::isDirty(): New overloaded method to check whether model
541 has any changes to submit. QTBUG-3108
543 * QSqlTableModel::setData() and setRecord() no longer revert pending changes
544 that fail upon resubmitting for edit strategies OnFieldChange and OnRowChange.
545 Instead, pending (failed) changes cause new changes inappropriate to the
546 edit strategy to be refused. The application should resolve or revert pending
547 changes. insertRows() and insertRecord() also respect the edit strategy.
549 * QSqlTableModel::setData() and setRecord() in OnRowChange no longer have the
550 side effect of submitting the cached row when invoked on a different row.
552 * QSqlDriver::subscribeToNotification, unsubscribeFromNotification,
553 subscribedToNotifications, isIdentifierEscaped, and stripDelimiters
554 are now virtual. Their xxxImplemenation counterparts have been removed
555 now that QSqlDriver subclasses can reimplement these directly.
557 ****************************************************************************
559 ****************************************************************************
563 * QVariant::Bool type now mapped to integers 0/1 in SQL instead of strings
564 'true' and 'false'. Sqlite does not have a boolean column type and it is
565 customary to use integer. QTBUG-23895
567 ****************************************************************************
568 * Platform Specific Changes *
569 ****************************************************************************
577 * Accessibility framework uses IAccessible2
578 * ANGLE can be used to provide Open GL ES 2.0 (see http://code.google.com/p/angleproject/)
584 Qt for Embedded Linux
585 ---------------------
592 ****************************************************************************
593 * Compiler Specific Changes *
594 ****************************************************************************
597 ****************************************************************************
599 ****************************************************************************
603 * Remove qttest_p4.prf file. From now on we should explicitly enable the
604 things from it which we want. Autotest .pro files should stop using
605 'load(qttest_p4)' and start using 'CONFIG+=testcase' instead.
610 * [QTBUG-8926] [QTBUG-20440] Properties of type QStringList now have
611 translation attributes which apply to all items.
612 They are by default translatable.
621 * [QTBUG-20785] The moc now has a -b<file> option to #include an additional
622 file at the beginning of the generated file.
633 * QMAKE_MOC_OPTIONS variable is now available for passing additional parameters
639 * The Mac OS X -dwarf2 configure argument has been removed. DWARF2 is always
640 used on Mac OS X now.
645 ****************************************************************************
647 ****************************************************************************
648 - The text codecs that were previously plugins are now built into QtCore.
650 ****************************************************************************
651 * Important Behavior Changes *
652 ****************************************************************************
656 * The implementation of QPointer has been changed to use QWeakPointer. The
657 old guard mechanism has been removed. This causes a slight change
658 in behavior when using QPointer:
660 * When using QPointer on a QWidget (or a subclass of QWidget), previously
661 the QPointer would be cleared by the QWidget destructor. Now, the QPointer
662 is cleared by the QObject destructor (since this is when QWeakPointers are
663 cleared). Any QPointers tracking a widget will NOT be cleared before the
664 QWidget destructor destroys the children for the widget being tracked.
668 * QUrl has been changed to operate only on percent-encoded
669 forms. Fully-decoded forms, where the percent character stands for itself,
670 are no longer possible. For that reason, the getters and setters with
671 "encoded" in the name are deprecated, except for QUrl::toEncoded() and
674 QUrl now operates in a mode where it decodes as much as it can of the
675 percent-encoding sequences. In addition, the setter methods possess a mode
676 in which a '%' character not part of a percent-encoding sequence will cause
677 the parser to correct the input. Therefore, most software will not require
678 changes to adapt, since the getter methods will continue returning the
679 components in their most-decoded form as they did before and the setter
680 methods will accept input as they did before..
682 The most notable difference is when dealing with
683 QUrl::toString(). Previously, this function would return percent characters
684 in the URL by themselves. Now, it will return "%25", like
689 * Definition of QVariant::UserType changed. Currently it is the same as
690 QMetaType::User, which means that it points to the first registered custom
691 type, instead of a nonexistent type.
695 * Interpretation of QMetaType::Void was changed. Before, in some cases
696 it was returned as an invalid type id, but sometimes it was used as a valid
697 type (C++ "void"). In Qt5, new QMetaType::UnknownType was introduced to
698 distinguish between these two. QMetaType::UnknownType is an invalid type id
699 signaling that a type is unknown to QMetaType, and QMetaType::Void
700 is a valid type id of C++ void type. The difference will be visible for
701 example in call to QMetaType::typeName(), this function will return null for
702 QMetaType::UnknownType and a pointer to "void" string for
704 Please, notice that QMetaType::UnknownType has value 0, which previously was
705 reserved for QMetaType::Void.
710 * The static function QMessageBox::question has changed the default argument
711 for buttons. Before the default was to have an Ok button. That is changed
712 to having a yes and a no button.