From bd0f3345a938b35ce6a12f6150373b0955b8dd12 Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Sun, 10 Jul 2011 15:24:15 -0500 Subject: Add Qt3 development HEAD version --- doc/html/keyfeatures30.html | 357 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 357 insertions(+) create mode 100644 doc/html/keyfeatures30.html (limited to 'doc/html/keyfeatures30.html') diff --git a/doc/html/keyfeatures30.html b/doc/html/keyfeatures30.html new file mode 100644 index 0000000..8a2258f --- /dev/null +++ b/doc/html/keyfeatures30.html @@ -0,0 +1,357 @@ + + + + + +Key Features in Qt 3.0 + + + + + + + +

Key Features in Qt 3.0

+ + + +

Qt 3.0 adds a lot of new features and improvements over the Qt 2.x +series. Some internals have undergone major redesign and new classes +and methods have been added. +

We have tried to keep the API of Qt 3.0 as compatible as possible with +the Qt 2.x series. For most applications only minor changes will be +needed to compile and run them successfully using Qt 3.0. +

One of the major new features that has been added in the 3.0 release +is a module allowing you to easily work with databases. The API is +platform independent and database neutral. This module is seamlessly +integrated into Qt Designer, greatly simplifying the process of +building database applications and using data aware widgets. +

+Other major new features include a plugin architecture. You can use +your own and third party plugins your own applications. +The Unicode support of Qt 2.x has been greatly enhanced, it now +includes full support for scripts written from right to left (e.g. +Arabic and Hebrew) and also provides improved support for Asian +languages. +

Many new classes have been added to the Qt Library. Amongst them are +classes that provide a docking architecture +(QDockArea/QDockWindow), a powerful rich text editor +(QTextEdit), a class to store and access application settings +(QSettings) and a class to create and communicate with processes +(QProcess). +

Apart from the changes in the library itself a lot has been done to +make the development of Qt applications with Qt 3.0 even easier than +before. Two new applications have been added: Qt Linguist is a tool to +help you translate your application into different languages; Qt +Assistant is an easy to use help browser for the Qt documentation that +supports bookmarks and can search by keyword. +

Another change concerns the Qt build system, which has been reworked +to make it a lot easier to port Qt to new platforms. You can use this +platform independent build system for your own applications. +

The Qt Library +

A large number of new features has been added to Qt 3.0. The following +list gives an overview of the most important new and changed aspects +of the Qt library. A full list of every new method follows the +overview. +

Database support +

One of the major new features in Qt 3.0 is the SQL +module that provides multiplatform access to SQL databases, +making database application programming with Qt seamless and portable. +The API, built with standard SQL, is database-neutral and software +development is independent of the underlying database. +

A collection of tightly focused C++ classes are provided to give the +programmer direct access to SQL databases. Developers can send raw SQL +to the database server or have the Qt SQL classes generate SQL queries +automatically. Drivers for Oracle, PostgreSQL, MySQL and ODBC are +available and writing new drivers is straightforward. +

Tying the results of SQL queries to GUI components is fully supported +by Qt's SQL widgets. These classes include a tabular data widget +(for spreadsheet-like data presentation with in-place editing), a +form-based data browser (which provides data navigation and edit +functions) and a form-based data viewer (which provides read-only +forms). This framework can be extended by using custom field editors, +allowing for example, a data table to use custom widgets for in-place +editing. The SQL module fully supports Qt's signal/slots mechanism, +making it easy for developers to include their own data validation and +auditing code. +

Qt Designer fully supports Qt's SQL module. All SQL widgets can be +laid out within Qt Designer, and relationships can be established +between controls visually. Many interactions can be defined purely in +terms of Qt's signals/slots mechanism directly in Qt Designer. +

Plugins +

The QLibrary class provides a platform independent wrapper for runtime +loading of shared libraries. QPluginManager makes it trivial to implement +plugin support in applications. The Qt library is able to load +additional styles, database drivers and text codecs from plugins. +

Qt Designer supports custom widgets in plugins, and will use the +widgets both when designing and previewing forms. +

See the plugins documentation. +

Rich text engine and editor +

The rich text engine originally introduced in Qt 2.0 has been further +optimized and extended to support editing. It allows editing formatted +text with different fonts, colors, paragraph styles, tables and +images. The editor supports different word wrap modes, command-based +undo/redo, multiple selections, drag and drop, and many other +features. The new QTextEdit engine is highly optimized for proccesing +and displaying large documents quickly and efficiently. +

Unicode +

Apart from the rich text engine, another new feature of Qt 3.0 that +relates to text handling is the greatly improved Unicode support. Qt +3.0 includes an implementation of the bidirectional algorithm (BiDi) +as defined in the Unicode standard and a shaping engine for Arabic, +which gives full native language support to Arabic and Hebrew speaking +people. At the same time the support for Asian languages has been +greatly enhanced. +

The support is almost transparent for the developer using Qt to +develop their applications. This means that developers who developed +applications using Qt 2.x will automatically gain the full support for +these languages when switching to Qt 3.0. Developers can rely on their +application to work for people using writing systems different from +Latin1, without having to worry about the complexities involved with +these scripts, as Qt takes care of this automatically. +

Docked and Floating Windows +

Qt 3.0 introduces the concept of Dock Windows and Dock Areas. Dock +windows are widgets, that can be attached to, and detached from, dock +areas. The commonest kind of dock window is a tool bar. Any number of +dock windows may be placed in a dock area. A main window can have dock +areas, for example, QMainWindow provides four dock areas (top, left, +bottom, right) by default. The user can freely move dock windows and +place them at a convenient place in a dock area, or drag them out of +the application and have them float freely as top level windows in +their own right. Dock windows can also be minimized or hidden. +

For developers, dock windows behave just like ordinary widgets. QToolbar +for example is now a specialized subclass of a dock window. The API +of QMainWindow and QToolBar is source compatible with Qt 2.x, so +existing code which uses these classes will continue to work. +

Regular Expressions +

Qt has always provided regular expression support, but that support +was pretty much limited to what was required in common GUI control +elements such as file dialogs. Qt 3.0 introduces a new regular +expression engine, QRegExp, that supports most of Perl's regex +features and is Unicode based. The most useful additions are support +for parentheses (capturing and non-capturing) and backreferences. +

Storing application settings +

Most programs will need to store some settings between runs, for +example, user selected fonts, colors and other preferences, or a list +of recently used files. The new QSettings class provides a platform +independent way to achieve this goal. The API makes it easy to store +and retrieve most of the basic data types used in Qt (such as basic +C++ types, strings, lists, colors, etc). The class uses the registry +on the Windows platform and traditional resource files on Unix. +

Creating and controlling other processes +

QProcess is a class that allows you to start other programs from +within a Qt application in a platform independent manner. It gives you +full control over the started program, for example you can redirect +the input and output of console applications. +

Accessibility +

Accessibility means making software usable and accessible to a wide +range of users, including those with disabilities. In Qt 3.0, most +widgets provide accessibility information for assistive tools that can +be used by a wide range of disabled users. Qt standard widgets like +buttons or range controls are fully supported. Support for complex +widgets, like e.g. QListView, is in development. Existing applications +that make use of standard widgets will become accessible just by using +Qt 3.0. +

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. +

XML Improvements +

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. +

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. +

SVG support +

SVG is a W3C standard for "Scalable Vector Graphics". Qt 3.0's XML +support means that QPicture can optionally generate and import static +SVG documents. All the SVG features that have an equivalent in +QPainter are supported. +

Multihead support +

Many professional applications, such as DTP and CAD software, are able +to display data on two or more monitors. In Qt 3.0 the QDesktopWidget +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. +

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. +

X11 specific enhancements +

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. +

The font handling on X11 has undergone major changes. QFont 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. +

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). +

Printing +

Printing support has been enhanced on all platforms. The QPrinter +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. +

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. +

QHttp +

This class provides a simple interface for HTTP downloads and uploads. +

Compatibility with the Standard Template Library (STL) +

Support for the C++ Standard Template Library has been added to the +Qt Template Library (QTL). 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()). +

Qt Designer +

Qt Designer was a pure dialog +editor in Qt 2.2 but has now been extended to provide the full +functionality of a GUI design tool. +

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. +

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. +

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. +

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. +

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, QWidgetFactory in the +QResource library. +

Qt Linguist +

Qt Linguist 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. +

Translation of a Qt application is a three-step process: +

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). +
Provide translations for the source texts in the *.ts file using +Qt Linguist. +
Run lrelease to obtain a light-weight message file (a *.qm file) +from the *.ts file, which provides very fast lookup for released +applications. +

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. +

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. +

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. +

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. +

Qt Assistant +

Thanks to the positive feedback we received about the help system +built into Qt Designer, we decided +to offer this part as a separate application called Qt Assistant. 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. +

qmake +

To ease portability we now provide the qmake 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. +

+ +

Trademarks +

Qt 3.3.8

+ -- cgit v1.2.3