Qt 4.2 introduces many new features as well as many improvements and

bugfixes over the 4.1.x series. For more details, see the online

documentation which is included in this distribution. The

documentation is also available at http://qt.nokia.com/doc/

The Qt version 4.2 series is binary compatible with the 4.1.x series.

Applications compiled for 4.1 will continue to run with 4.2.

The Qtopia Core version 4.2 series is binary compatible with the 4.1.x

series except for some parts of the device handling API, as detailed

in Platform Specific Changes below.

****************************************************************************

*                           General                                        *

****************************************************************************

New features

------------

- QCalendarWidget provides a standard monthly calendar widget with date

  selection features.

- QCleanlooksStyle provides the new Cleanlooks style, a clone of the GNOME

  ClearLooks style, giving Qt applications a native look on GNOME desktops.

- QCompleter provides facilities for auto completion in text entry widgets.

- QDataWidgetMapper can be used to make widgets data-aware by mapping them

  to sections of an item model.

- QDesktopServices provides desktop integration features, such as support

  for opening URLs using system services.

- QDialogButtonBox is used in dialogs to ensure that buttons are placed

  according to platform-specific style guidelines.

- QFileSystemWatcher enables applications to monitor files and directories

  for changes.

- QFontComboBox provides a standard font selection widget for document

  processing applications.

- QGraphicsView and related classes provide the Graphics View framework, a

  replacement for Qt 3's canvas module that provides an improved API, enhanced

  rendering, and more responsive handling of large numbers of canvas items.

- QGLFramebufferObject encapsulates OpenGL framebuffer objects.

- QMacPasteboardMime handles Pasteboard access on Qt/Mac. This obsoletes

  QMacMime as the underlying system has changed to support Apple's new

  Pasteboard Manager. Any old QMacMime objects will not be used.

- QNetworkInterface represents a network interface, providing information

  about the host's IP addresses and network interfaces.

- QResource provides static functions that control resource lookup and

  provides a way to navigate resources directly without levels of

  indirection through QFile/QFileEngine.

- QSystemTrayIcon allows applications to provide their own icon in the

  system tray.

- QTimeLine gives developers access to a standard time line class with which

  to create widget animations.

- The QtDBus module provides inter-process communication on platforms

  that support the D-BUS protocol.

- The QUndo* classes in Qt's Undo framework provide undo/redo functionality

  for applications.

- Support for the Glib event loop to enable integration between Qt and non-Qt

  applications on the GNOME desktop environment.

- Improved Accessibility for item-based views and QTextEdit.

- Support for main window animations and tabbed dock widgets.

- Added an SVG icon engine to enable SVG drawings to be used by QIcon.

- Widgets can now be styled according to rules specified in a style sheet,

  using a syntax familiar to users of Cascading Style Sheets (CSS). Style

  sheets are set using the QWidget::styleSheet property.

- Introduced a new key mapper system which improves the shortcut system by

  only testing the real possible shortcuts, such as Ctrl+Shift+= and Ctrl++

  on an English keyboard.

- Improved and enhanced QMessageBox to support native look and feel on many

  common platforms.

- Experimental support for Qt usage reporting ("metered licenses") on Linux,

  Windows and Mac OS X. Reporting is disabled by default.

- A screen magnification utility, pixeltool, is provided. It is designed to help

  with the process of fine-tuning styles and user interface features.

- New qrand() and qsrand() functions to provide thread safe equivalents to

  rand() and srand().

General improvements

--------------------

- Item views

      * Selections are maintained when the layout of the model changes

        (e.g., due to sorting).

      * Convenience views can perform dynamic sorting of items when the data

        in items changes.

      * QStandardItem provides an item-based API for use with

        QStandardItemModel and the model/view item view classes.

      * QStandardItemModel API provides a classic item-based approach to

        working with models.

      * Single selection item views on Mac OS X cannot change their current

        item without changing the current selection when using keyboard

        navigation.

- Plastique style has improved support for palettes, and now requires

  XRender support on X11 for alpha transparency.

- Tulip containers

      * Added typedefs for STL compatability.

      * Added function overloads to make the API easier to use.

- Added the Q3TextStream class for compatiblity with Qt 3 and to assist with

  porting projects.

- OpenGL paint engine

      * Added support for all composition modes of QPainter natively using

        OpenGL.

      * Fixed a case where very large polygons failed to render correctly.

      * Ensured that glClear() is only called in begin() if the

        QGLWidget::autoFillBackground() property is true.

      * Ensured that a buffer swap is only performed in end() if

        QGLWidget::autoBufferSwap() is true.

      * Improved text drawing speed and quality.

- Raster paint engine

      * Fixed blending of 8 bit indexed images with alpha values.

      * Fixed drawing onto QImages that were wider than 2048 pixels.

      * Fixed alpha-blending and anti-aliasing on ARGB32 images.

      * Improved point drawing performance.

      * Fixed issue where lines were drawn between coordinates that were

        rounded instead of truncated.

      * Ensured that setClipRegion(QRegion()) clips away all painting

        operations as originally intended.

Third party components

----------------------

- Dropped support for MySQL version 3.

- Updated Qt's SQLite version to 3.3.6.

- Updated Qt's FreeType version to 2.2.1.

- Updated Qt's libpng version to 1.2.10.

Build System

------------

- Auto-detect PostgreSQL and MySQL using pg_config and mysql_config on UNIX

  based systems in the configure script

- Added "-system-sqlite" option to configure to use the system's SQLite

  library instead of Qt's SQLite version.

- Added QT_ASCII_CAST_WARNINGS define that will output a warning on implicit

  ascii to Unicode conversion when set. Only works if the compiler supports

  deprecated API warnings.

- Added Q_REQUIRED_RESULT to some functions. This macro triggers a warning

  if the result of a function is discarded. Currently only supported by gcc.

- Qt/X11, Qt/Mac and Qtopia Core only:

     * Added all QT_NO_* defines to the build key.

- Qt/X11 and Qtopia Core only:

     * As in Qt 3, the configure script enables the -release option by

       default, causing the Qt libraries to be built with optimizations. If

       configured with the -debug option, the debug builds no longer result

       in libraries with the _debug suffix.

       On modern systems, flags are added to the Qt build to also

       generate debugging information, which is then stored in a

       separate .debug file. The additional debug information does not

       affect the performance of the optimized code and tools like gdb

       and valgrind automatically pick up the separate .debug

       files. This way it is possible to get useful backtraces even

       with release builds of Qt.

     * Removed the last vestiges of the module options in the configure

       script, previously they were available but did not function.

     * Implemented a -build option in the configure script to conditionally

       compile only certain sections of Qt.

     * Made it possible to build Qt while having "xcode" set as your

       QMAKESPEC on OSX.

- Windows only:

     * Populated the build key, as done on all the other platforms.

     * Fixed dependency generation in Visual Studio Solutions (.sln)

       created by qmake.

     * Added missing platforms to the Visual Studio project generator (X64,

       SH3DSP and EBC).

     * Made UIC3 use a temporary file for long command lines.

     * Removed the object file (.o) conflicts with MinGW that appeared when

       embedding a native resource file which was named the same as a normal

       source file.

     * Fixed mkspec detection when generating project files outside of QTDIR.

     * Removed compiler warnings with MinGW g++ 3.4.5.

****************************************************************************

*                          Library                                         *

****************************************************************************

- QAbstractButton

      * Returns QPalette::Button and QPalette::ButtonText for

        backgroundRole() and foregroundRole(), respectively, rather than

        QPalette::Background and QPalette::Foreground.

      * Ensured that nextCheckState() is called only when there is a state

        change.

- QAbstractItemModel

      * When dropping rows only insert rows that were actually dropped, not

        the continuous row count from first to last.

      * Added a supportedDragActions property to be used by

        QAbstractItemView when starting a drag.

      * When updating changed persistent indexes, ignore those that haven't

        actually changed.

      * Fixed endian issue with createIndex().

      * Added FixedString matching for match().

      * Changed the sorting algorithm to use a stable sort.

      * Added persistentIndexList() function.

- QAbstractItemView

      * Added possibility to copy elements to clipboard on read-only views.

      * Improved handling of QAbstractItemModel::supportedDropActions().

      * Ensured that the current item is selected when using keyboard

        search.

      * Ensured that the view starts with a valid current index.

      * Ensured that data is only committed in currentChanged() if the

        editor is not persistent.

      * Fixed crash that occurred when a modal dialogs was opened when

        closing an editor.

      * Added verticalScrollMode and horizontalScrollMode properties.

      * Added setItemDelegateForRow() and setItemDelegateForColumn().

      * Ensured that existing models are disconnected properly when

        replaced.

      * Ensured that the doubleClicked() signal is only emitted when the

        left button has been double-clicked.

      * Changed setSelection(...) to work when given a non-normalized

        rectangle.

      * Fixed regression for shift-selections in ExtendedSelection for

        all views.

      * Added dragDropMode property and implemented move support in all of

        the views and models.

      * For edit triggers SelectedClicked and DoubleClicked, only trigger

        editing when the left button is clicked.

      * Trigger SelectedClicked editing on mouse release, not mouse press.

      * Suppressed the doubleClicked() signal in cases where the clicks

        happened on two different items.

      * Enabled keyboard search to be programmatically reset by calling

        keyboardSearch() with an empty string as argument.

      * Don't allow drops on items that don't have the Qt::ItemIsDropEnabled

        flag set.

      * Added modelAboutToBeReset() and layoutAboutToBeChanged() signals.

      * Suppressed assertion in dropMimeData() for cases where mimeTypes()

        returns an empty list.

      * Ensured consistent behavior of drag and drop when rootIndex() is a

        valid model index.

      * Made it possible to check a checkbox with only a single click when

        using the CurrentChanged edit trigger.

      * Ensured that WhatsThis events are propagated when the relevant item

        doesn't have a valid "What's This?" value.

      * Added PositionAtCenter scrollHint.

      * Added support to allow items to be checked and unchecked using the

        keyboard.

      * Added support for keypad navigation.

- QAbstractProxyModel

      * Added default implementations for data(), headerData() and flags()

- QAbstractScrollArea

      * Added ability to set a corner widget.

      * Added ability to set scroll bar widgets.

      * Added support for custom scroll bars.

- QAbstractSpinBox

      * Added a hasAcceptableInput() property.

      * Ensured that fixup/validate are called for third party subclasses of

        QAbstractSpinBox as well.

      * Fixed geometry issues when toggling frames on and off for spinboxes.

      * Added a property for correctionMode.

      * Added a property for acceleration.

- QAbstractPrintDialog

      * Fixed handling of existing printer options so that storage of page

        ranges using setFromTo() works as expected when printing in PDF format.

- QAction

      * Added the setAutoRepeat(bool) function to disable auto-repeating

        actions on keyboard shortcuts.

- QApplication

      * Added saveStateRequest() and commitDataRequest() signals so that

        QApplication does not need to be subclassed to enable session

        management in an application.

      * Added the styleSheet property to get/set the application style sheet.

      * Support sending key events to non-widget objects.

      * Ensured that argc and argv as passed to the QApplication constructor

        will always be zero-terminated on all platforms after QApplication

        consumes command line options for itself.

- QBrush

      * Added a constructor that accepts a QImage.

- QButtonGroup

      * Added pressed() and released() signals.

      * Fixed a bug caused by removing buttons from button groups. Removed the

        internal mapping as well.

      * Ensured that checkedButton() returns the correct value with

        non-exclusive groups.

- QClipboard

      * Added support for find text buffer.

- QColor

      * Fixed corruption in setRed(), setGreen() and setBlue() for HSV/CMYK

        colors.

- QComboBox

      * Fixed drawing issues related to certain FocusPolicy values.

      * Ensured that the ItemFlags of an Item (ItemIsEnabled,...) are

        respected.

      * Fixed cases where the popup could be shown completly on screen, but

        weren't.

      * Added the InsertAlphabetically insert policy.

      * Fixed case where a QPixmap could not be displayed using a QIcon.

      * Fixed the type of the modelColumn property from bool to int.

      * Updated documentation to clarify the differences between activated(),

        highlighted() and currentIndexChanged(), and describe what they

        actually mean.

      * Updated the behavior to ensure that, if the combobox isn't editable,

        the Qt::DisplayRole rather than the Qt::EditRole is used to query the

        model.

- QCoreApplication

      * Added flags to enable/disable application-wide features such as

        delayed widget creation.

- QCursor

      * Added support for the newly added Qt::OpenHandCursor and

        Qt::ClosedHandCursor enum values.

- QDate

      * Support dates all the way down to Julian Day 1 (2 January 4713 B.C.)

        using the Julian calendar when appropriate.

- QDateTime

      * Fixed parsing issue in fromString(const QString &, Qt::DateFormat).

- QDateTimeEdit

      * Added the calendarPopup property to enable date selection using the

        new QCalendarWidget class.

      * Added a setSelectedSection() function to allow the currently selected

        section to be programmatically set.

- QDesktopWidget

      * Remove a potential out-of-bounds read.

- QDialog

      * Improved stability in cases where the default button is deleted.

- QDir

      * Improved support for i18n file paths in QDir::tempPath().

      * Improved support for UNC paths when the application is run from a

        share.

      * Ensured that mkpath() properly supports UNC paths.

      * Obsoleted QDir::convertSeparators().

      * Introduced QDir::toNativeSeparators() and QDir::fromNativeSeparators().

      * Added a QDebug streaming operator.

- QDirModel

      * Fixed conversion from bytes to larger units in QDirModel in the file

        size display.

      * Remove hardcoded filtering of the '.' and '..' entries.

- QErrorMessage

      * Made qtHandler() work in cases where the message handler is invoked

        from threads other than the GUI thread.

- QEvent

      * Added the KeyboardLayoutChange event type which is sent when the

        keyboard layout changes.

- QFile

      * Improved support for UNC paths when the application is run from a

        share.

      * Added support for physical drives (e.g., "//./Physical01").

      * Ensured that QFile::error() and QIODevice::errorString() are set

        whenever possible when errors occur.

      * Renamed readLink() to symLinkTarget().

- QFileDialog