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QT 下载资料仅供参考

widgets, like e.g. <a href="qlistview.html">QListView</a>, is in development. Existing applications
that make use of standard widgets will become accessible just by using
Qt 3.0.
<p> Qt uses the Active Accessibility infrastructure on Windows, and needs
the MSAA SDK, which is part of most platform SDKs. With improving
standardization of accessibility on other platforms, Qt will support
assistive technologies on other systems, too.
<p> <h3> XML Improvements
</h3>
<a name="1-10"></a><p> The XML framework introduced in Qt 2.2 has been vastly improved. Qt
2.2 already supported level 1 of the Document Object Model (DOM), a
W3C standard for accessing and modifying XML documents.  Qt 3.0 has
added support for DOM Level 2 and XML namespaces.
<p> The XML parser has been extended to allow incremental parsing of XML
documents. This allows you to start parsing the document directly
after the first parts of the data have arrived, and to continue
whenever new data is available.  This is especially useful if the XML
document is read from a slow source, e.g. over the network, as it
allows the application to start working on the data at a very early
stage.
<p> <h3> SVG support
</h3>
<a name="1-11"></a><p> SVG is a W3C standard for "Scalable Vector Graphics". Qt 3.0's XML
support means that <a href="qpicture.html">QPicture</a> can optionally generate and import static
SVG documents. All the SVG features that have an equivalent in
<a href="qpainter.html">QPainter</a> are supported.
<p> <h3> Multihead support
</h3>
<a name="1-12"></a><p> Many professional applications, such as DTP and CAD software, are able
to display data on two or more monitors. In Qt 3.0 the <a href="qdesktopwidget.html">QDesktopWidget</a>
class provides the application with runtime information about the
number and geometry of the desktops on the different monitors and such
allows applications to efficiently use a multi-monitor setup.
<p> The virtual desktop of Mac OS X, Windows 98, and 2000 is supported, as well
as the traditional multi-screen and the newer Xinerama multihead setups on
X11.
<p> <h3> X11 specific enhancements
</h3>
<a name="1-13"></a><p> Qt 3.0 now complies with the NET WM Specification, recently adopted
by KDE 2.0.  This allows easy integration and proper execution with
desktop environments that support the NET WM specification.
<p> The font handling on X11 has undergone major changes.  <a href="qfont.html">QFont</a> no longer
has a one-to-one relation with window system fonts.  QFont is now a
logical font that can load multiple window system fonts to simplify
Unicode text display.  This completely removes the burden of
changing/setting fonts for a specific locale/language from the
programmer.  For end-users, any font can be used in any locale.  For
example, a user in Norway will be able to see Korean text without
having to set their locale to Korean.
<p> Qt 3.0 also supports the new render extension recently added to
XFree86. This adds support for anti aliased text and pixmaps with
alpha channel (semi transparency) on the systems that support the
rendering extension (at the moment XFree 4.0.3 and later).
<p> <h3> Printing
</h3>
<a name="1-14"></a><p> Printing support has been enhanced on all platforms. The <a href="qprinter.html">QPrinter</a>
class now supports setting a virtual resolution for the painting
process. This makes WYSIWYG printing trivial, and also allows you to
take full advantage of the high resolution of a printer when painting
on it.
<p> The postscript driver built into Qt and used on Unix has been greatly
enhanced. It supports the embedding of true/open type and type1 fonts
into the document, and can correctly handle and display Unicode.
Support for fonts built into the printer has been enhanced and Qt now
knows about the most common printer fonts used for Asian languages.
<p> <h3> <a href="qhttp.html">QHttp</a>
</h3>
<a name="1-15"></a><p> This class provides a simple interface for HTTP downloads and uploads.
<p> <h3> Compatibility with the Standard Template Library (STL)
</h3>
<a name="1-16"></a><p> Support for the C++ Standard Template Library has been added to the
<a href="qt-template-lib.html">Qt Template Library (QTL)</a>.  The QTL
classes now contain appropriate copy constructors and typedefs so that
they can be freely mixed with other STL containers and algorithms.  In
addition, new member functions have been added to QTL template classes
which correspond to STL-style naming conventions (e.g., push_back()).
<p> <h2> Qt Designer
</h2>
<a name="2"></a><p> <a href="designer-manual.html">Qt Designer</a> was a pure dialog
editor in Qt 2.2 but has now been extended to provide the full
functionality of a GUI design tool.
<p> This includes the ability to lay out main windows with menus and
toolbars. Actions can be edited within Qt Designer and then plugged
into toolbars and menu bars via drag and drop. Splitters can now be
used in a way similar to layouts to group widgets horizontally or
vertically.
<p> In Qt 2.2, many of the dialogs created by Qt Designer had to be
subclassed to implement functionality beyond the predefined signal and
slot connections. Whilst the subclassing approach is still fully supported,
Qt Designer now offers an alternative: a plugin for editing 
slots. The editor offers features such as syntax highlighting,
completion, parentheses matching and incremental search.
<p> The functionality of Qt Designer can now be extended via plugins.
Using Qt Designer's interface or by implementing one of the provided
interfaces in a plugin, a two way communication between plugin and Qt
Designer can be established. This functionality is used to implement
plugins for custom widgets, so that they can be used as real widgets
inside the designer.
<p> Basic support for project management has been added. This allows you
to read and edit *.pro files, add and remove files to/from the project
and do some global operations on the project. You can now open the
project file and have one-click access to all the *.ui forms in the
project.
<p> In addition to generating code via uic, Qt Designer now supports the
dynamic creation of widgets directly from XML user interface
description files (*.ui files) at runtime. This eliminates the need of
recompiling your application when the GUI changes, and could be used
to enable your customers to do their own customizations. Technically,
the feature is provided by a new class, <a href="qwidgetfactory.html">QWidgetFactory</a> in the
QResource library.
<p> <h2> Qt Linguist
</h2>
<a name="3"></a><p> <a href="linguist-manual.html">Qt Linguist</a> is a GUI utility to
support translating the user-visible text in applications written with
Qt. It comes with two command-line tools: lupdate and lrelease.
<p> Translation of a Qt application is a three-step process:
<p> <ul>
<li> Run lupdate to extract user-visible text from the C++ source
code of the Qt application, resulting in a translation source file
(a *.ts file).
<li> Provide translations for the source texts in the *.ts file using
Qt Linguist.
<li> Run lrelease to obtain a light-weight message file (a *.qm file)
from the *.ts file, which provides very fast lookup for released
applications.
</ul>
<p> Qt Linguist is a tool suitable for use by translators. Each
user-visible (source) text is characterized by the text itself, a
context (usually the name of the C++ class containing the text), and
an optional comment to help the translator. The C++ class name will
usually be the name of the relevant dialog, and the comment will often
contain instructions that describe how to navigate to the relevant
dialog.
<p> You can create phrase books for Qt Linguist to provide common
translations to help ensure consistency and to speed up the
translation process. Whenever a translator navigates to a new text to
translate, Qt Linguist uses an intelligent algorithm to provide a list
of possible translations: the list is composed of relevant text from
any open phrase books and also from identical or similar text that has
already been translated.
<p> Once a translation is complete it can be marked as "done"; such
translations are included in the *.qm file. Text that has not been
"done" is included in the *.qm file in its original form. Although Qt
Linguist is a GUI application with dock windows and mouse control,
toolbars, etc., it has a full set of keyboard shortcuts to make
translation as fast and efficient as possible.
<p> When the Qt application that you're developing evolves (e.g. from
version 1.0 to version 1.1), the utility lupdate merges the source
texts from the new version with the previous translation source file,
reusing existing translations. In some typical cases, lupdate may
suggest translations. These translations are marked as unfinished, so
you can easily find and check them.
<p> <h2> Qt Assistant
</h2>
<a name="4"></a><p> Thanks to the positive feedback we received about the <a href="helpsystem.html#help-system">help system</a>
built into <a href="designer-manual.html">Qt Designer</a>, we decided
to offer this part as a separate application called <a href="assistant.html">Qt Assistant</a>. Qt Assistant can be used to
browse the Qt class documentation as well as the manuals for Qt
Designer and Qt Linguist. It offers index searching, a contents
overview, bookmarks history and incremental search. Qt Assistant is
used by both Qt Designer and Qt Linguist for browsing their help
documentation.
<p> <h2> qmake
</h2>
<a name="5"></a><p> To ease portability we now provide the <a href="qmake-manual.html">qmake</a> utility to replace tmake. QMake is a C++ version of
tmake which offers additional functionallity that is difficult to
reproduce in tmake. Trolltech uses qmake in its build system for Qt
and related products and we have released it as free software.
<p> 
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<td>Copyright &copy; 2002 
<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.5</div>
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