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What's New in Qt 4.7Qt 4.7 provides many improvements and enhancements over the previous releases in the Qt 4 series. This document covers the most important features in this release, separated by category. A list of other Qt 4 features can be found on the What's New in Qt 4 page. Declarative UI Development with Qt Quick
Qt 4.7 introduces Qt Quick, the Qt UI Creation Kit. that enables the creation of dynamic user interfaces, easier and more effective than possible with existing UI technologies. This UI Creation Kit consists of three technologies:
Network Bearer ManagementBearer Management controls the connectivity state of the system. The new Bearer Management API in the QtNetwork module allows the application to identify whether the system is online and how many interfaces there are, as well as start and stop interfaces, or roam transparently between access points. QNetworkAccessManager uses this API for HTTP level roaming. Feature Improvements in QtWebKitThe QGraphicsWebView class has a new tiled backing store, which improves scrolling and zooming performance. You can even create animated zoom-in or zoom-out effects (see QWebSettings::TiledBackingStoreEnabled). On mobile platforms, it is often useful to avoid displaying separate scrollbars for iframes and framesets. If you switch on frame flattening, QtWebKit will resize frames to fit their content to avoid separate scrollbars (see QWebSettings::FrameFlatteningEnabled). Qt 4.7 adds support for accelerated compositing, which enhances the performance of CSS animations and transitions. Read more in this blog. For hybrid QtWebKit and C++ projects, Qt 4.7 has added support for transporting QPixmaps between Qt C++ and WebKit. We have also improved the documentation for hybrid development. Read more here: The QtWebKit Bridge. QtWebKit Performance BenchmarksWe have introduced a set of performance benchmarks for QtWebKit, and made numerous improvements in rendering performance, page loading performance, scrolling performance and CSS performance. Here are some examples from the benchmarks run on a 64-bit Linux workstation with the raster graphics system. In a benchmark that measures the scrolling performance on popular websites, we found out that Qt 4.7.0 on this platform is 350% faster than Qt 4.6.0, thanks to several rendering related improvements. Our page loading benchmark shows an improvement of 16% in Qt 4.7.0 from Qt 4.6.0. This is due to improvements in text layout speed, image decoding, resource loading and event handling. Several CSS animation benchmarks indicate a speed improvement of 31% from Qt 4.6.0 to Qt 4.7.0. These benchmarks are effectively showing the improvement we get from accelerated compositing (see above). Other Performance Related ImprovementsIn addition to the QtWebKit module, performance has been a focus area in Qt 4.7 throughout the Qt framework. Here are a couple of examples about performance related feature improvements. On Mac OS X, Qt now uses a different widget implementation (called "alien widgets"), which improves the responsiveness of applications that have complex user interfaces with several widgets. Qt 4.7 introduces the QStaticText class, which can be used to improve text rendering performance. More info is available from this blog. The QPainter class has a new API for rendering pixmap fragments (QPainter::drawPixmapFragments), which can improve the rendering performance of applications that need to render pixmap fragments. Qt 4.7 has an updated version of the JavaScriptCore engine for the QtScript module, which improves JavaScript execution performance. New Classes, Functions, Macros, etc.Links to new classes, elements, functions, macros, and other items introduced in Qt 4.7. New Classes
New Member FunctionsClass QWebFrame:
Class QAuthenticator:
Class QAudioFormat:
Class QGLShader:
Class QGLShaderProgram:
Class QGraphicsScale:
Class QFileSystemModel:
Class VideoWidget:
Class QState:
Class QPlainTextEdit:
Class QAudioDeviceInfo:
Class QNetworkRequest:
Class QGraphicsItem:
Class QGraphicsObject:
Class QIconEngineV2:
Class QDBusMessage:
Class QNetworkAccessManager:
Class QWizard:
Class QScriptEngine:
New Global Functions
New QML Elements
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