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diff --git a/doc/src/declarative/basicelements.qdoc b/doc/src/declarative/basicelements.qdoc new file mode 100644 index 0000000..0146591 --- /dev/null +++ b/doc/src/declarative/basicelements.qdoc @@ -0,0 +1,114 @@ +/**************************************************************************** +** +** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:FDL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Free Documentation License +** Alternatively, this file may be used under the terms of the GNU Free +** Documentation License version 1.3 as published by the Free Software +** Foundation and appearing in the file included in the packaging of this +** file. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! +\page qmlbasicelements.html +\ingroup qml-features +\contentspage QML Features +\previouspage QML Features +\nextpage {QML Basic Types}{Data Types} + +\title QML Basic Elements + +QML's basic elements allow the easy inclusion of objects into the +scene. + +\section1 Basic Elements +This is a list of some of the elements readily available for users. +\list +\o \l {Item} +\o \l {Rectangle} +\o \l {Image} +\o \l {Text} +\o \l {TextInput} +\o \l {TextEdit} +\o \l {FocusScope} +\o \l {Component} +\o \l {MouseArea} +\endlist + +For a complete list of QML elements, please visit the \l {QML Elements} page. + +\section1 Properties and Qt Declarative Module + +When using QML elements, keep in mind that elements may possess properties that +other elements also possess. This is because QML and its underlying engine is +implemented in C++ using Qt. More importantly, the chain of property inheritance +is directly due to QML's use of the \l {Qt Declarative Module} and Qt's +\l {Meta-Object System}{meta-object} and \l {The Property System}{property} systems. For example, visual elements that have C++ implementation are sublcasses of +\l {QDeclarativeItem}. As a result, elements such as \l {Rectangle} and +\l {Text} elements inherit properties such as \c clip and \c smooth. + +\section1 Item Element + +Many QML elements inherit \l Item properties. \c Item possesses important properties +such as \c focus, \c children, and dimension properties such as \c width and +\c height. Although \c Item has physical properties, it is not a visual element. +Using \c Item as the top-level QML element (as the screen) will not produce a +visual result, use the \l {Rectangle} element instead. Use the \c Item to create +opacity effects, such as when creating an invisible container to hold other +components. + +\section1 Rectangle Element + +The \l Rectangle element is the basic visual element, for displaying different +types of items onto the screen. The \c Rectangle is customizable and utilizes +other elements such as \l Gradient and \l BorderImage for displaying advanced +customized graphics. + +\section1 Image Element + +To insert an image into a QML scene, merely declare an \l Image element. The +\c Image element can load images in formats supported by Qt. + +\section1 Text Elements + +The \l Text and \l TextEdit elements display formatted text onto the screen. +\c TextEdit features multi-line editing while the \l TextInput element is for +single line text input. + +\keyword qml-top-level-component +\section1 Using Elements as the Top-Level Component + +For creating components (or displaying a simple scene), there are different +elements that could be used as the top-level component. To display a simple scene, +a \l Rectangle as the top-level component may suffice. \l Rectangle, +\l FocusScope, \l Component, \l {QML:QtObject} {QtObject}, \l Item, are some of +the commonly used elements as the top-level component. + +When importing components, the top-level component is important because the +top-level component's properties are the only properties exposed to the parent. + +For example, a \c Button component may be implemented using different elements as +its top-level component. When this component is loaded into another QML scene, +the component will retain the top-level component's properties. If a non-visual +component is the top-level component, the visual properties should be aliased to +the top-level to display the component properly. + +For more information on how to build upon QML elements, see the +\l{Importing Reusable Components} document. +*/ |